From 750b5028a18de8a958db63849b5bae84180dad84 Mon Sep 17 00:00:00 2001
From: jaortega <jaortega>
Date: Wed, 1 Nov 2000 22:53:21 +0000
Subject:

---
 .cvsignore                      |   13 +
 AUTHORS                         |    4 +
 COPYING                         |  339 ++++++++
 ChangeLog                       |    0
 INSTALL                         |  179 ++++
 Makefile.am                     |   15 +
 NEWS                            |   26 +
 README                          |   20 +
 THANKS                          |    8 +
 TODO                            |   11 +
 acconfig.h                      |   10 +
 aclocal.m4                      |  838 +++++++++++++++++++
 autogen.sh                      |   91 ++
 configure.in                    |   56 ++
 doc/.cvsignore                  |    8 +
 doc/Makefile.am                 |   15 +
 doc/gpl.texi                    |  396 +++++++++
 doc/html/.cvsignore             |   16 +
 doc/html/Makefile.am            |   14 +
 doc/html/download.html          |  105 +++
 doc/html/index.html             |  104 +++
 doc/mdk.texi                    | 1763 +++++++++++++++++++++++++++++++++++++++
 mixlib/.cvsignore               |    5 +
 mixlib/Makefile.am              |   37 +
 mixlib/mix.c                    |   63 ++
 mixlib/mix.h                    |   65 ++
 mixlib/mix_code_file.c          |  320 +++++++
 mixlib/mix_code_file.h          |  102 +++
 mixlib/mix_device.c             |  217 +++++
 mixlib/mix_device.h             |  135 +++
 mixlib/mix_file.c               |  142 ++++
 mixlib/mix_file.h               |   61 ++
 mixlib/mix_ins.c                |  258 ++++++
 mixlib/mix_ins.h                |  192 +++++
 mixlib/mix_io.c                 |  220 +++++
 mixlib/mix_io.h                 |  123 +++
 mixlib/mix_parser.c             |  519 ++++++++++++
 mixlib/mix_parser.h             |  110 +++
 mixlib/mix_scanner.l            |  497 +++++++++++
 mixlib/mix_symbol_table.c       |  139 +++
 mixlib/mix_symbol_table.h       |   99 +++
 mixlib/mix_types.c              |  543 ++++++++++++
 mixlib/mix_types.h              |  283 +++++++
 mixlib/mix_vm.c                 |  445 ++++++++++
 mixlib/mix_vm.h                 |  171 ++++
 mixlib/mix_vm_dump.c            |  194 +++++
 mixlib/mix_vm_dump.h            |   92 ++
 mixlib/testsuite/.cvsignore     |   27 +
 mixlib/testsuite/Makefile.am    |   26 +
 mixlib/testsuite/mix_device_t.c |   76 ++
 mixlib/testsuite/mix_ins_t.c    |   79 ++
 mixlib/testsuite/mix_parser_t.c |   85 ++
 mixlib/testsuite/mix_types_t.c  |  361 ++++++++
 mixlib/testsuite/mix_vm_ins_t.c |  500 +++++++++++
 mixlib/testsuite/test.h         |   44 +
 mixlib/xmix_io.c                |   57 ++
 mixlib/xmix_io.h                |   64 ++
 mixlib/xmix_parser.h            |   96 +++
 mixlib/xmix_vm.c                |  568 +++++++++++++
 mixlib/xmix_vm.h                |  111 +++
 mixutils/.cvsignore             |    6 +
 mixutils/Makefile.am            |   18 +
 mixutils/mixasm.c               |  126 +++
 mixutils/mixasm_comp.c          |   72 ++
 mixutils/mixasm_comp.h          |   35 +
 mixutils/mixvm.c                |  148 ++++
 mixutils/mixvm_command.c        |  867 +++++++++++++++++++
 mixutils/mixvm_command.h        |   38 +
 mixutils/mixvm_loop.c           |   66 ++
 po/.cvsignore                   |    7 +
 po/ChangeLog                    |    3 +
 po/POTFILES.in                  |   10 +
 po/ca.po                        |  506 +++++++++++
 samples/.cvsignore              |   25 +
 samples/Makefile.am             |   14 +
 samples/hello.mixal             |   11 +
 samples/primes.mixal            |   53 ++
 77 files changed, 13162 insertions(+)
 create mode 100644 .cvsignore
 create mode 100644 AUTHORS
 create mode 100644 COPYING
 create mode 100644 ChangeLog
 create mode 100644 INSTALL
 create mode 100644 Makefile.am
 create mode 100644 NEWS
 create mode 100644 README
 create mode 100644 THANKS
 create mode 100644 TODO
 create mode 100644 acconfig.h
 create mode 100644 aclocal.m4
 create mode 100755 autogen.sh
 create mode 100644 configure.in
 create mode 100644 doc/.cvsignore
 create mode 100644 doc/Makefile.am
 create mode 100644 doc/gpl.texi
 create mode 100644 doc/html/.cvsignore
 create mode 100644 doc/html/Makefile.am
 create mode 100644 doc/html/download.html
 create mode 100644 doc/html/index.html
 create mode 100644 doc/mdk.texi
 create mode 100644 mixlib/.cvsignore
 create mode 100644 mixlib/Makefile.am
 create mode 100644 mixlib/mix.c
 create mode 100644 mixlib/mix.h
 create mode 100644 mixlib/mix_code_file.c
 create mode 100644 mixlib/mix_code_file.h
 create mode 100644 mixlib/mix_device.c
 create mode 100644 mixlib/mix_device.h
 create mode 100644 mixlib/mix_file.c
 create mode 100644 mixlib/mix_file.h
 create mode 100644 mixlib/mix_ins.c
 create mode 100644 mixlib/mix_ins.h
 create mode 100644 mixlib/mix_io.c
 create mode 100644 mixlib/mix_io.h
 create mode 100644 mixlib/mix_parser.c
 create mode 100644 mixlib/mix_parser.h
 create mode 100644 mixlib/mix_scanner.l
 create mode 100644 mixlib/mix_symbol_table.c
 create mode 100644 mixlib/mix_symbol_table.h
 create mode 100644 mixlib/mix_types.c
 create mode 100644 mixlib/mix_types.h
 create mode 100644 mixlib/mix_vm.c
 create mode 100644 mixlib/mix_vm.h
 create mode 100644 mixlib/mix_vm_dump.c
 create mode 100644 mixlib/mix_vm_dump.h
 create mode 100644 mixlib/testsuite/.cvsignore
 create mode 100644 mixlib/testsuite/Makefile.am
 create mode 100644 mixlib/testsuite/mix_device_t.c
 create mode 100644 mixlib/testsuite/mix_ins_t.c
 create mode 100644 mixlib/testsuite/mix_parser_t.c
 create mode 100644 mixlib/testsuite/mix_types_t.c
 create mode 100644 mixlib/testsuite/mix_vm_ins_t.c
 create mode 100644 mixlib/testsuite/test.h
 create mode 100644 mixlib/xmix_io.c
 create mode 100644 mixlib/xmix_io.h
 create mode 100644 mixlib/xmix_parser.h
 create mode 100644 mixlib/xmix_vm.c
 create mode 100644 mixlib/xmix_vm.h
 create mode 100644 mixutils/.cvsignore
 create mode 100644 mixutils/Makefile.am
 create mode 100644 mixutils/mixasm.c
 create mode 100644 mixutils/mixasm_comp.c
 create mode 100644 mixutils/mixasm_comp.h
 create mode 100644 mixutils/mixvm.c
 create mode 100644 mixutils/mixvm_command.c
 create mode 100644 mixutils/mixvm_command.h
 create mode 100644 mixutils/mixvm_loop.c
 create mode 100644 po/.cvsignore
 create mode 100644 po/ChangeLog
 create mode 100644 po/POTFILES.in
 create mode 100644 po/ca.po
 create mode 100644 samples/.cvsignore
 create mode 100644 samples/Makefile.am
 create mode 100644 samples/hello.mixal
 create mode 100644 samples/primes.mixal

diff --git a/.cvsignore b/.cvsignore
new file mode 100644
index 0000000..a4fec3d
--- /dev/null
+++ b/.cvsignore
@@ -0,0 +1,13 @@
+.emacs.desktop
+Makefile
+Makefile.in
+config.cache
+config.h
+config.h.in
+config.log
+config.status
+configure
+intl
+mdk-0.1.tar.gz
+stamp-h
+stamp-h.in
diff --git a/AUTHORS b/AUTHORS
new file mode 100644
index 0000000..23231f5
--- /dev/null
+++ b/AUTHORS
@@ -0,0 +1,4 @@
+Authors of mdk.
+See also the files THANKS and ChangeLog.
+
+jose antonio ortega ruiz designed and implemented mdk.
diff --git a/COPYING b/COPYING
new file mode 100644
index 0000000..a43ea21
--- /dev/null
+++ b/COPYING
@@ -0,0 +1,339 @@
+		    GNU GENERAL PUBLIC LICENSE
+		       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+                          675 Mass Ave, Cambridge, MA 02139, USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+			    Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+		    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term "modification".)  Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices
+    stating that you changed the files and the date of any change.
+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
+    interactive use in the most ordinary way, to print or display an
+    announcement including an appropriate copyright notice and a
+    notice that there is no warranty (or else, saying that you provide
+    a warranty) and that users may redistribute the program under
+    these conditions, and telling the user how to view a copy of this
+    License.  (Exception: if the Program itself is interactive but
+    does not normally print such an announcement, your work based on
+    the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable
+    source code, which must be distributed under the terms of Sections
+    1 and 2 above on a medium customarily used for software interchange; or,
+
+    b) Accompany it with a written offer, valid for at least three
+    years, to give any third party, for a charge no more than your
+    cost of physically performing source distribution, a complete
+    machine-readable copy of the corresponding source code, to be
+    distributed under the terms of Sections 1 and 2 above on a medium
+    customarily used for software interchange; or,
+
+    c) Accompany it with the information you received as to the offer
+    to distribute corresponding source code.  (This alternative is
+    allowed only for noncommercial distribution and only if you
+    received the program in object code or executable form with such
+    an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it.  For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable.  However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+  4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+  5. You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+  6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+  7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+			    NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+		     END OF TERMS AND CONDITIONS
+
+	Appendix: How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) 19yy  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) 19yy name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.
diff --git a/ChangeLog b/ChangeLog
new file mode 100644
index 0000000..e69de29
diff --git a/INSTALL b/INSTALL
new file mode 100644
index 0000000..421bc5c
--- /dev/null
+++ b/INSTALL
@@ -0,0 +1,179 @@
+Basic Installation
+==================
+
+    For more information specific to this package, please read the README
+file. This source code distribution  is autoconfiguring and you should be 
+able to compile it and install it without manual interventions such as 
+editing Makefiles, configuration files, and so on. These are generic 
+instructions for people who are not familiar with installing autoconfiguring
+software.
+
+The simplest way to compile this package is to enter the source code
+main directory and do the following:
+   
+  1. Configure the source code by typing:
+        % sh ./configure
+
+     If you're planning to install the package into your home directory
+     or to a location other than `/usr/local' then add the flag
+     `--prefix=PATH' to `configure'. For example, if your home directory  
+     is `/home/luser' you can configure the package to install itself there
+     by invoking:
+        % sh ./configure --prefix=/home/luser
+     
+     While running, `configure' prints some messages telling which
+     features is it checking for. 
+
+  2. Compile the package by typing:
+        % make
+     Running `make' takes a while. If this is a very large package, now
+     is the time to go make some coffee.
+     
+  3. Some packages are bundled with self-tests for source-code 
+     verification. If this package includes such tests, you can 
+     optionally run them after compilation by typing 
+        % make check
+
+  4. Type `make install' to install the programs and any data files and
+     documentation. Type `make uninstall' to undo the installation.
+     During installation, the following files go to the following directories:
+        Executables          -> /prefix/bin
+        Libraries            -> /prefix/lib
+        Public header files  -> /prefix/include
+        Man pages            -> /prefix/man/man?
+        Info files           -> /prefix/info
+     where `prefix' is either `/usr/local' or the PATH that you specified
+     in the `--prefix' flag.
+
+     If any of these directories do not presently exist, they will be
+     created on demand. 
+
+     If you are installing in your home directory make sure that 
+     `/home/luser/bin' is in your path. If you're using the bash shell
+     add this line at the end of your .cshrc file:
+        PATH="/home/luser/bin:${PATH}"
+        export PATH
+     If you are using csh or tcsh, then use this line instead:
+        setenv PATH /home/luser/bin:${PATH}
+     By prepending your home directory to the rest of the PATH you can
+     override systemwide installed software with your own custom installation.
+
+  5. You can remove the program binaries and object files from the
+     source code directory by typing `make clean'.  To also remove the
+     files that `configure' created (so you can compile the package for
+     a different kind of computer), type `make distclean'.
+
+Compiler configuration
+======================
+
+   The `configure' shell script is responsible for choosing and configuring
+the compiler(s). 
+
+The following options allow you to specify whether you
+want to enable or disable various debugging mechanisms:
+
+`--with-warnings'
+      Make the compilers very picky about warnings. Try this whenever you
+      write new code since it may catch a few bugs. This is not active by
+      default because all too often warnings can be too picky and scare
+      the end-user.
+
+`--disable-assert'
+      Compile without using assertions. This results in faster code,
+      but should not be used during developerment, or to run `make check'
+      which depends on assertions. It should only be used for production
+      runs on code that you believe is bug free.
+
+All programs are compiled with optimization level 2 by default (-O2).
+Occasionally that confuses the debugger when code is inlined. To disable
+optimization and enable debugging, set the shell environment variables
+CFLAGS, CXXFLAGS, FFLAGS to `-g'. On the bash shell, you can do this
+like this:
+  $ export CFLAGS="-g"
+  $ export CXXFLAGS="-g"
+  $ export FFLAGS="-g"
+On the tcsh shell, use the `setenv' command instead:
+  % setenv CFLAGS "-g"
+  ...etc...
+For other shell, please consult your shell's documentation.
+
+Similarly, you can increase the optimization level by assigning these
+variables to "-g -O3". 
+
+The following options allow you to reconsider the `configure' shell script's
+choice of Fortran compilers.
+
+`--with-f2c'
+      Compile the Fortran code by translating it to C, even if a native
+      Fortran compiler is available. A copy of the f2c translator should be
+      bundled in the distribution. It will be compiled and then used to 
+      compile your Fortran code.
+`--with-g77'
+      Compile the Fortran code with g77 even if a proprietary Fortran  
+      compiler is available
+`--with-f77=F77'
+      Compile the Fortran code with the specified Fortran compiler.
+
+Depending on what languages the package uses, some of these options may
+or may not be available. To see what is available, type:
+    % sh ./configure --help
+
+About the configure script
+==========================
+ 
+   The `configure' shell script attempts to guess correct values for
+various system-dependent variables used during compilation.  It uses
+those values to create a `Makefile' in each directory of the package.
+It may also create one or more `.h' files containing system-dependent
+definitions.  Finally, it creates a shell script `config.status' that
+you can run in the future to recreate the current configuration, a file
+`config.cache' that saves the results of its tests to speed up
+reconfiguring, and a file `config.log' containing compiler output
+(useful mainly for debugging `configure').
+
+   If you need to do unusual things to compile the package, please try
+to figure out how `configure' could check whether to do them, and mail
+diffs or instructions to the address given in the `README' so they can
+be considered for the next release.  If at some point `config.cache'
+contains results you don't want to keep, you may remove or edit it.
+
+   The file `configure.in' is used to create `configure' by a program
+called `autoconf'.  You only need `configure.in' if you want to change
+it or regenerate `configure' using a newer version of `autoconf'.
+
+Advanced installation options.
+==============================
+
+   The `configure' script also understands the following more advanced
+options, to handle situations for which `--prefix' alone is not sufficient.
+
+   You can specify separate installation prefixes for
+architecture-specific files and architecture-independent files.  If you
+give `configure' the option `--exec-prefix=PATH', the package will use
+PATH as the prefix for installing programs and libraries.
+Documentation and other data files will still use the regular prefix.
+
+   In addition, if you use an unusual directory layout you can give
+options like `--bindir=PATH' to specify different values for particular
+kinds of files.  Run `configure --help' for a list of the directories
+you can set and what kinds of files go in them.
+
+   If the package supports it, you can cause programs to be installed
+with an extra prefix or suffix on their names by giving `configure' the
+option `--program-prefix=PREFIX' or `--program-suffix=SUFFIX'.
+
+Optional Features
+=================
+
+   Some packages pay attention to `--enable-FEATURE' options to
+`configure', where FEATURE indicates an optional part of the package.
+They may also pay attention to `--with-PACKAGE' options, where PACKAGE
+is something like `gnu-as' or `x' (for the X Window System).  The
+`README' should mention any `--enable-' and `--with-' options that the
+package recognizes.
+
+   For packages that use the X Window System, `configure' can usually
+find the X include and library files automatically, but if it doesn't,
+you can use the `configure' options `--x-includes=DIR' and
+`--x-libraries=DIR' to specify their locations.
+
diff --git a/Makefile.am b/Makefile.am
new file mode 100644
index 0000000..c57ce00
--- /dev/null
+++ b/Makefile.am
@@ -0,0 +1,15 @@
+## Process this file with automake to produce Makefile.in
+
+# Copyright (C) 2000 Jose Antonio Ortega Ruiz <jaortega@retemail.es>
+#  
+# This file is free software; as a special exception the author gives
+# unlimited permission to copy and/or distribute it, with or without 
+# modifications, as long as this notice is preserved.
+# 
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+EXTRA_DIST = ABOUT-NLS  autogen.sh configure
+SUBDIRS = po intl doc mixlib mixutils samples
+
diff --git a/NEWS b/NEWS
new file mode 100644
index 0000000..1b3ca02
--- /dev/null
+++ b/NEWS
@@ -0,0 +1,26 @@
+mdk -- History of visible changes.
+
+Copyright (C) 2000, jose antonio ortega ruiz <jaortega@acm.org>
+See the end for copying conditions.
+
+Please send mdk bug reports to jaortega@acm.org.
+
+Version 0.1
+
+* Initial version
+
+-------------------------------------------------------
+Copying information:
+
+Copyright (C) 2000, jose antonio ortega ruiz <jaortega@acm.org>
+
+   Permission is granted to anyone to make or distribute verbatim copies
+   of this document as received, in any medium, provided that the
+   copyright notice and this permission notice are preserved,
+   thus giving the recipient permission to redistribute in turn.
+
+   Permission is granted to distribute modified versions
+   of this document, or of portions of it,
+   under the above conditions, provided also that they
+   carry prominent notices stating who last changed them.
+
diff --git a/README b/README
new file mode 100644
index 0000000..475387b
--- /dev/null
+++ b/README
@@ -0,0 +1,20 @@
+Welcome to MDK.
+
+MDK stands for MIX Development Kit and provides tools for developing
+and executing, in a MIX virtual machine, MIXAL programs. The MIX
+is Donald Knuth's mythical computer, described in the first volume
+of _The Art of Computer Programming_ (Addison Wesley, 1997), which
+is programmed using MIXAL, the MIX Assembly language.
+
+Currently, MDK includes a MIXAL assembler, mixasm, and a MIX virtual
+machine, mixvm, with a command line interface.
+
+MDK is free software. Please see the file COPYING for details.
+For documentation, please see the files in the doc subdirectory.
+For building and installation instructions please see the INSTALL file.
+For sample MIXAL programs, please see the samples subdirectory.
+For translations (MDK uses GNU's gettext), please see the po subdirectory[0].
+
+--
+[0] New translations are welcome. If you'd like to contribute one,
+    please contact the author, jaortega@acm.org.
\ No newline at end of file
diff --git a/THANKS b/THANKS
new file mode 100644
index 0000000..7f5b5a4
--- /dev/null
+++ b/THANKS
@@ -0,0 +1,8 @@
+MDK THANKS file
+
+MDK has originally been written by jose antonio ortega ruiz.
+Many people have further contributed to MDK by reporting problems, 
+suggesting various improvements, or submitting actual code. Here is
+a list of these people. Help me keep it complete and exempt of errors.
+
+* nobody yet :-)
diff --git a/TODO b/TODO
new file mode 100644
index 0000000..288e2e2
--- /dev/null
+++ b/TODO
@@ -0,0 +1,11 @@
+- mixvm trace command outputting executed instructions
+- allow MIXAL instructions as commands at the mixvm prompt
+  (e.g. MIX > exec LDA 2000)
+- improve detection of pseudoinstructions in mixasm listing files
+- include timing statistics
+
+* allow abbrevs of mixvm commands (e.g. ed file -> edit file)
+* ncurses based frontend
+* add GTK/GNOME support (see gaby's config hacks for making it optional)
+
+
diff --git a/acconfig.h b/acconfig.h
new file mode 100644
index 0000000..06f5f49
--- /dev/null
+++ b/acconfig.h
@@ -0,0 +1,10 @@
+#undef PACKAGE
+#undef VERSION
+#undef HAVE_LIBSM
+#undef HAVE_CATGETS
+#undef HAVE_GETTEXT
+#undef HAVE_LC_MESSAGES
+#undef HAVE_STPCPY
+#undef ENABLE_NLS
+#undef LOCALEDIR
+
diff --git a/aclocal.m4 b/aclocal.m4
new file mode 100644
index 0000000..bd51429
--- /dev/null
+++ b/aclocal.m4
@@ -0,0 +1,838 @@
+dnl aclocal.m4 generated automatically by aclocal 1.4
+
+dnl Copyright (C) 1994, 1995-8, 1999 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl This program is distributed in the hope that it will be useful,
+dnl but WITHOUT ANY WARRANTY, to the extent permitted by law; without
+dnl even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+dnl PARTICULAR PURPOSE.
+
+# Like AC_CONFIG_HEADER, but automatically create stamp file.
+
+AC_DEFUN(AM_CONFIG_HEADER,
+[AC_PREREQ([2.12])
+AC_CONFIG_HEADER([$1])
+dnl When config.status generates a header, we must update the stamp-h file.
+dnl This file resides in the same directory as the config header
+dnl that is generated.  We must strip everything past the first ":",
+dnl and everything past the last "/".
+AC_OUTPUT_COMMANDS(changequote(<<,>>)dnl
+ifelse(patsubst(<<$1>>, <<[^ ]>>, <<>>), <<>>,
+<<test -z "<<$>>CONFIG_HEADERS" || echo timestamp > patsubst(<<$1>>, <<^\([^:]*/\)?.*>>, <<\1>>)stamp-h<<>>dnl>>,
+<<am_indx=1
+for am_file in <<$1>>; do
+  case " <<$>>CONFIG_HEADERS " in
+  *" <<$>>am_file "*<<)>>
+    echo timestamp > `echo <<$>>am_file | sed -e 's%:.*%%' -e 's%[^/]*$%%'`stamp-h$am_indx
+    ;;
+  esac
+  am_indx=`expr "<<$>>am_indx" + 1`
+done<<>>dnl>>)
+changequote([,]))])
+
+# Do all the work for Automake.  This macro actually does too much --
+# some checks are only needed if your package does certain things.
+# But this isn't really a big deal.
+
+# serial 1
+
+dnl Usage:
+dnl AM_INIT_AUTOMAKE(package,version, [no-define])
+
+AC_DEFUN(AM_INIT_AUTOMAKE,
+[AC_REQUIRE([AC_PROG_INSTALL])
+PACKAGE=[$1]
+AC_SUBST(PACKAGE)
+VERSION=[$2]
+AC_SUBST(VERSION)
+dnl test to see if srcdir already configured
+if test "`cd $srcdir && pwd`" != "`pwd`" && test -f $srcdir/config.status; then
+  AC_MSG_ERROR([source directory already configured; run "make distclean" there first])
+fi
+ifelse([$3],,
+AC_DEFINE_UNQUOTED(PACKAGE, "$PACKAGE", [Name of package])
+AC_DEFINE_UNQUOTED(VERSION, "$VERSION", [Version number of package]))
+AC_REQUIRE([AM_SANITY_CHECK])
+AC_REQUIRE([AC_ARG_PROGRAM])
+dnl FIXME This is truly gross.
+missing_dir=`cd $ac_aux_dir && pwd`
+AM_MISSING_PROG(ACLOCAL, aclocal, $missing_dir)
+AM_MISSING_PROG(AUTOCONF, autoconf, $missing_dir)
+AM_MISSING_PROG(AUTOMAKE, automake, $missing_dir)
+AM_MISSING_PROG(AUTOHEADER, autoheader, $missing_dir)
+AM_MISSING_PROG(MAKEINFO, makeinfo, $missing_dir)
+AC_REQUIRE([AC_PROG_MAKE_SET])])
+
+#
+# Check to make sure that the build environment is sane.
+#
+
+AC_DEFUN(AM_SANITY_CHECK,
+[AC_MSG_CHECKING([whether build environment is sane])
+# Just in case
+sleep 1
+echo timestamp > conftestfile
+# Do `set' in a subshell so we don't clobber the current shell's
+# arguments.  Must try -L first in case configure is actually a
+# symlink; some systems play weird games with the mod time of symlinks
+# (eg FreeBSD returns the mod time of the symlink's containing
+# directory).
+if (
+   set X `ls -Lt $srcdir/configure conftestfile 2> /dev/null`
+   if test "[$]*" = "X"; then
+      # -L didn't work.
+      set X `ls -t $srcdir/configure conftestfile`
+   fi
+   if test "[$]*" != "X $srcdir/configure conftestfile" \
+      && test "[$]*" != "X conftestfile $srcdir/configure"; then
+
+      # If neither matched, then we have a broken ls.  This can happen
+      # if, for instance, CONFIG_SHELL is bash and it inherits a
+      # broken ls alias from the environment.  This has actually
+      # happened.  Such a system could not be considered "sane".
+      AC_MSG_ERROR([ls -t appears to fail.  Make sure there is not a broken
+alias in your environment])
+   fi
+
+   test "[$]2" = conftestfile
+   )
+then
+   # Ok.
+   :
+else
+   AC_MSG_ERROR([newly created file is older than distributed files!
+Check your system clock])
+fi
+rm -f conftest*
+AC_MSG_RESULT(yes)])
+
+dnl AM_MISSING_PROG(NAME, PROGRAM, DIRECTORY)
+dnl The program must properly implement --version.
+AC_DEFUN(AM_MISSING_PROG,
+[AC_MSG_CHECKING(for working $2)
+# Run test in a subshell; some versions of sh will print an error if
+# an executable is not found, even if stderr is redirected.
+# Redirect stdin to placate older versions of autoconf.  Sigh.
+if ($2 --version) < /dev/null > /dev/null 2>&1; then
+   $1=$2
+   AC_MSG_RESULT(found)
+else
+   $1="$3/missing $2"
+   AC_MSG_RESULT(missing)
+fi
+AC_SUBST($1)])
+
+# Add --enable-maintainer-mode option to configure.
+# From Jim Meyering
+
+# serial 1
+
+AC_DEFUN(AM_MAINTAINER_MODE,
+[AC_MSG_CHECKING([whether to enable maintainer-specific portions of Makefiles])
+  dnl maintainer-mode is disabled by default
+  AC_ARG_ENABLE(maintainer-mode,
+[  --enable-maintainer-mode enable make rules and dependencies not useful
+                          (and sometimes confusing) to the casual installer],
+      USE_MAINTAINER_MODE=$enableval,
+      USE_MAINTAINER_MODE=no)
+  AC_MSG_RESULT($USE_MAINTAINER_MODE)
+  AM_CONDITIONAL(MAINTAINER_MODE, test $USE_MAINTAINER_MODE = yes)
+  MAINT=$MAINTAINER_MODE_TRUE
+  AC_SUBST(MAINT)dnl
+]
+)
+
+# Define a conditional.
+
+AC_DEFUN(AM_CONDITIONAL,
+[AC_SUBST($1_TRUE)
+AC_SUBST($1_FALSE)
+if $2; then
+  $1_TRUE=
+  $1_FALSE='#'
+else
+  $1_TRUE='#'
+  $1_FALSE=
+fi])
+
+
+# serial 1
+
+# @defmac AC_PROG_CC_STDC
+# @maindex PROG_CC_STDC
+# @ovindex CC
+# If the C compiler in not in ANSI C mode by default, try to add an option
+# to output variable @code{CC} to make it so.  This macro tries various
+# options that select ANSI C on some system or another.  It considers the
+# compiler to be in ANSI C mode if it handles function prototypes correctly.
+#
+# If you use this macro, you should check after calling it whether the C
+# compiler has been set to accept ANSI C; if not, the shell variable
+# @code{am_cv_prog_cc_stdc} is set to @samp{no}.  If you wrote your source
+# code in ANSI C, you can make an un-ANSIfied copy of it by using the
+# program @code{ansi2knr}, which comes with Ghostscript.
+# @end defmac
+
+AC_DEFUN(AM_PROG_CC_STDC,
+[AC_REQUIRE([AC_PROG_CC])
+AC_BEFORE([$0], [AC_C_INLINE])
+AC_BEFORE([$0], [AC_C_CONST])
+dnl Force this before AC_PROG_CPP.  Some cpp's, eg on HPUX, require
+dnl a magic option to avoid problems with ANSI preprocessor commands
+dnl like #elif.
+dnl FIXME: can't do this because then AC_AIX won't work due to a
+dnl circular dependency.
+dnl AC_BEFORE([$0], [AC_PROG_CPP])
+AC_MSG_CHECKING(for ${CC-cc} option to accept ANSI C)
+AC_CACHE_VAL(am_cv_prog_cc_stdc,
+[am_cv_prog_cc_stdc=no
+ac_save_CC="$CC"
+# Don't try gcc -ansi; that turns off useful extensions and
+# breaks some systems' header files.
+# AIX			-qlanglvl=ansi
+# Ultrix and OSF/1	-std1
+# HP-UX			-Aa -D_HPUX_SOURCE
+# SVR4			-Xc -D__EXTENSIONS__
+for ac_arg in "" -qlanglvl=ansi -std1 "-Aa -D_HPUX_SOURCE" "-Xc -D__EXTENSIONS__"
+do
+  CC="$ac_save_CC $ac_arg"
+  AC_TRY_COMPILE(
+[#include <stdarg.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+/* Most of the following tests are stolen from RCS 5.7's src/conf.sh.  */
+struct buf { int x; };
+FILE * (*rcsopen) (struct buf *, struct stat *, int);
+static char *e (p, i)
+     char **p;
+     int i;
+{
+  return p[i];
+}
+static char *f (char * (*g) (char **, int), char **p, ...)
+{
+  char *s;
+  va_list v;
+  va_start (v,p);
+  s = g (p, va_arg (v,int));
+  va_end (v);
+  return s;
+}
+int test (int i, double x);
+struct s1 {int (*f) (int a);};
+struct s2 {int (*f) (double a);};
+int pairnames (int, char **, FILE *(*)(struct buf *, struct stat *, int), int, int);
+int argc;
+char **argv;
+], [
+return f (e, argv, 0) != argv[0]  ||  f (e, argv, 1) != argv[1];
+],
+[am_cv_prog_cc_stdc="$ac_arg"; break])
+done
+CC="$ac_save_CC"
+])
+if test -z "$am_cv_prog_cc_stdc"; then
+  AC_MSG_RESULT([none needed])
+else
+  AC_MSG_RESULT($am_cv_prog_cc_stdc)
+fi
+case "x$am_cv_prog_cc_stdc" in
+  x|xno) ;;
+  *) CC="$CC $am_cv_prog_cc_stdc" ;;
+esac
+])
+
+
+dnl AM_PROG_LEX
+dnl Look for flex, lex or missing, then run AC_PROG_LEX and AC_DECL_YYTEXT
+AC_DEFUN(AM_PROG_LEX,
+[missing_dir=ifelse([$1],,`cd $ac_aux_dir && pwd`,$1)
+AC_CHECK_PROGS(LEX, flex lex, "$missing_dir/missing flex")
+AC_PROG_LEX
+AC_DECL_YYTEXT])
+
+# Macro to add for using GNU gettext.
+# Ulrich Drepper <drepper@cygnus.com>, 1995.
+#
+# This file can be copied and used freely without restrictions.  It can
+# be used in projects which are not available under the GNU Public License
+# but which still want to provide support for the GNU gettext functionality.
+# Please note that the actual code is *not* freely available.
+
+# serial 5
+
+AC_DEFUN(AM_WITH_NLS,
+  [AC_MSG_CHECKING([whether NLS is requested])
+    dnl Default is enabled NLS
+    AC_ARG_ENABLE(nls,
+      [  --disable-nls           do not use Native Language Support],
+      USE_NLS=$enableval, USE_NLS=yes)
+    AC_MSG_RESULT($USE_NLS)
+    AC_SUBST(USE_NLS)
+
+    USE_INCLUDED_LIBINTL=no
+
+    dnl If we use NLS figure out what method
+    if test "$USE_NLS" = "yes"; then
+      AC_DEFINE(ENABLE_NLS)
+      AC_MSG_CHECKING([whether included gettext is requested])
+      AC_ARG_WITH(included-gettext,
+        [  --with-included-gettext use the GNU gettext library included here],
+        nls_cv_force_use_gnu_gettext=$withval,
+        nls_cv_force_use_gnu_gettext=no)
+      AC_MSG_RESULT($nls_cv_force_use_gnu_gettext)
+
+      nls_cv_use_gnu_gettext="$nls_cv_force_use_gnu_gettext"
+      if test "$nls_cv_force_use_gnu_gettext" != "yes"; then
+        dnl User does not insist on using GNU NLS library.  Figure out what
+        dnl to use.  If gettext or catgets are available (in this order) we
+        dnl use this.  Else we have to fall back to GNU NLS library.
+	dnl catgets is only used if permitted by option --with-catgets.
+	nls_cv_header_intl=
+	nls_cv_header_libgt=
+	CATOBJEXT=NONE
+
+	AC_CHECK_HEADER(libintl.h,
+	  [AC_CACHE_CHECK([for gettext in libc], gt_cv_func_gettext_libc,
+	    [AC_TRY_LINK([#include <libintl.h>], [return (int) gettext ("")],
+	       gt_cv_func_gettext_libc=yes, gt_cv_func_gettext_libc=no)])
+
+	   if test "$gt_cv_func_gettext_libc" != "yes"; then
+	     AC_CHECK_LIB(intl, bindtextdomain,
+	       [AC_CACHE_CHECK([for gettext in libintl],
+		 gt_cv_func_gettext_libintl,
+		 [AC_CHECK_LIB(intl, gettext,
+		  gt_cv_func_gettext_libintl=yes,
+		  gt_cv_func_gettext_libintl=no)],
+		 gt_cv_func_gettext_libintl=no)])
+	   fi
+
+	   if test "$gt_cv_func_gettext_libc" = "yes" \
+	      || test "$gt_cv_func_gettext_libintl" = "yes"; then
+	      AC_DEFINE(HAVE_GETTEXT)
+	      AM_PATH_PROG_WITH_TEST(MSGFMT, msgfmt,
+		[test -z "`$ac_dir/$ac_word -h 2>&1 | grep 'dv '`"], no)dnl
+	      if test "$MSGFMT" != "no"; then
+		AC_CHECK_FUNCS(dcgettext)
+		AC_PATH_PROG(GMSGFMT, gmsgfmt, $MSGFMT)
+		AM_PATH_PROG_WITH_TEST(XGETTEXT, xgettext,
+		  [test -z "`$ac_dir/$ac_word -h 2>&1 | grep '(HELP)'`"], :)
+		AC_TRY_LINK(, [extern int _nl_msg_cat_cntr;
+			       return _nl_msg_cat_cntr],
+		  [CATOBJEXT=.gmo
+		   DATADIRNAME=share],
+		  [CATOBJEXT=.mo
+		   DATADIRNAME=lib])
+		INSTOBJEXT=.mo
+	      fi
+	    fi
+	])
+
+        if test "$CATOBJEXT" = "NONE"; then
+	  AC_MSG_CHECKING([whether catgets can be used])
+	  AC_ARG_WITH(catgets,
+	    [  --with-catgets          use catgets functions if available],
+	    nls_cv_use_catgets=$withval, nls_cv_use_catgets=no)
+	  AC_MSG_RESULT($nls_cv_use_catgets)
+
+	  if test "$nls_cv_use_catgets" = "yes"; then
+	    dnl No gettext in C library.  Try catgets next.
+	    AC_CHECK_LIB(i, main)
+	    AC_CHECK_FUNC(catgets,
+	      [AC_DEFINE(HAVE_CATGETS)
+	       INTLOBJS="\$(CATOBJS)"
+	       AC_PATH_PROG(GENCAT, gencat, no)dnl
+	       if test "$GENCAT" != "no"; then
+		 AC_PATH_PROG(GMSGFMT, gmsgfmt, no)
+		 if test "$GMSGFMT" = "no"; then
+		   AM_PATH_PROG_WITH_TEST(GMSGFMT, msgfmt,
+		    [test -z "`$ac_dir/$ac_word -h 2>&1 | grep 'dv '`"], no)
+		 fi
+		 AM_PATH_PROG_WITH_TEST(XGETTEXT, xgettext,
+		   [test -z "`$ac_dir/$ac_word -h 2>&1 | grep '(HELP)'`"], :)
+		 USE_INCLUDED_LIBINTL=yes
+		 CATOBJEXT=.cat
+		 INSTOBJEXT=.cat
+		 DATADIRNAME=lib
+		 INTLDEPS='$(top_builddir)/intl/libintl.a'
+		 INTLLIBS=$INTLDEPS
+		 LIBS=`echo $LIBS | sed -e 's/-lintl//'`
+		 nls_cv_header_intl=intl/libintl.h
+		 nls_cv_header_libgt=intl/libgettext.h
+	       fi])
+	  fi
+        fi
+
+        if test "$CATOBJEXT" = "NONE"; then
+	  dnl Neither gettext nor catgets in included in the C library.
+	  dnl Fall back on GNU gettext library.
+	  nls_cv_use_gnu_gettext=yes
+        fi
+      fi
+
+      if test "$nls_cv_use_gnu_gettext" = "yes"; then
+        dnl Mark actions used to generate GNU NLS library.
+        INTLOBJS="\$(GETTOBJS)"
+        AM_PATH_PROG_WITH_TEST(MSGFMT, msgfmt,
+	  [test -z "`$ac_dir/$ac_word -h 2>&1 | grep 'dv '`"], msgfmt)
+        AC_PATH_PROG(GMSGFMT, gmsgfmt, $MSGFMT)
+        AM_PATH_PROG_WITH_TEST(XGETTEXT, xgettext,
+	  [test -z "`$ac_dir/$ac_word -h 2>&1 | grep '(HELP)'`"], :)
+        AC_SUBST(MSGFMT)
+	USE_INCLUDED_LIBINTL=yes
+        CATOBJEXT=.gmo
+        INSTOBJEXT=.mo
+        DATADIRNAME=share
+	INTLDEPS='$(top_builddir)/intl/libintl.a'
+	INTLLIBS=$INTLDEPS
+	LIBS=`echo $LIBS | sed -e 's/-lintl//'`
+        nls_cv_header_intl=intl/libintl.h
+        nls_cv_header_libgt=intl/libgettext.h
+      fi
+
+      dnl Test whether we really found GNU xgettext.
+      if test "$XGETTEXT" != ":"; then
+	dnl If it is no GNU xgettext we define it as : so that the
+	dnl Makefiles still can work.
+	if $XGETTEXT --omit-header /dev/null 2> /dev/null; then
+	  : ;
+	else
+	  AC_MSG_RESULT(
+	    [found xgettext program is not GNU xgettext; ignore it])
+	  XGETTEXT=":"
+	fi
+      fi
+
+      # We need to process the po/ directory.
+      POSUB=po
+    else
+      DATADIRNAME=share
+      nls_cv_header_intl=intl/libintl.h
+      nls_cv_header_libgt=intl/libgettext.h
+    fi
+    AC_LINK_FILES($nls_cv_header_libgt, $nls_cv_header_intl)
+    AC_OUTPUT_COMMANDS(
+     [case "$CONFIG_FILES" in *po/Makefile.in*)
+        sed -e "/POTFILES =/r po/POTFILES" po/Makefile.in > po/Makefile
+      esac])
+
+
+    # If this is used in GNU gettext we have to set USE_NLS to `yes'
+    # because some of the sources are only built for this goal.
+    if test "$PACKAGE" = gettext; then
+      USE_NLS=yes
+      USE_INCLUDED_LIBINTL=yes
+    fi
+
+    dnl These rules are solely for the distribution goal.  While doing this
+    dnl we only have to keep exactly one list of the available catalogs
+    dnl in configure.in.
+    for lang in $ALL_LINGUAS; do
+      GMOFILES="$GMOFILES $lang.gmo"
+      POFILES="$POFILES $lang.po"
+    done
+
+    dnl Make all variables we use known to autoconf.
+    AC_SUBST(USE_INCLUDED_LIBINTL)
+    AC_SUBST(CATALOGS)
+    AC_SUBST(CATOBJEXT)
+    AC_SUBST(DATADIRNAME)
+    AC_SUBST(GMOFILES)
+    AC_SUBST(INSTOBJEXT)
+    AC_SUBST(INTLDEPS)
+    AC_SUBST(INTLLIBS)
+    AC_SUBST(INTLOBJS)
+    AC_SUBST(POFILES)
+    AC_SUBST(POSUB)
+  ])
+
+AC_DEFUN(AM_GNU_GETTEXT,
+  [AC_REQUIRE([AC_PROG_MAKE_SET])dnl
+   AC_REQUIRE([AC_PROG_CC])dnl
+   AC_REQUIRE([AC_PROG_RANLIB])dnl
+   AC_REQUIRE([AC_ISC_POSIX])dnl
+   AC_REQUIRE([AC_HEADER_STDC])dnl
+   AC_REQUIRE([AC_C_CONST])dnl
+   AC_REQUIRE([AC_C_INLINE])dnl
+   AC_REQUIRE([AC_TYPE_OFF_T])dnl
+   AC_REQUIRE([AC_TYPE_SIZE_T])dnl
+   AC_REQUIRE([AC_FUNC_ALLOCA])dnl
+   AC_REQUIRE([AC_FUNC_MMAP])dnl
+
+   AC_CHECK_HEADERS([argz.h limits.h locale.h nl_types.h malloc.h string.h \
+unistd.h sys/param.h])
+   AC_CHECK_FUNCS([getcwd munmap putenv setenv setlocale strchr strcasecmp \
+strdup __argz_count __argz_stringify __argz_next])
+
+   if test "${ac_cv_func_stpcpy+set}" != "set"; then
+     AC_CHECK_FUNCS(stpcpy)
+   fi
+   if test "${ac_cv_func_stpcpy}" = "yes"; then
+     AC_DEFINE(HAVE_STPCPY)
+   fi
+
+   AM_LC_MESSAGES
+   AM_WITH_NLS
+
+   if test "x$CATOBJEXT" != "x"; then
+     if test "x$ALL_LINGUAS" = "x"; then
+       LINGUAS=
+     else
+       AC_MSG_CHECKING(for catalogs to be installed)
+       NEW_LINGUAS=
+       for lang in ${LINGUAS=$ALL_LINGUAS}; do
+         case "$ALL_LINGUAS" in
+          *$lang*) NEW_LINGUAS="$NEW_LINGUAS $lang" ;;
+         esac
+       done
+       LINGUAS=$NEW_LINGUAS
+       AC_MSG_RESULT($LINGUAS)
+     fi
+
+     dnl Construct list of names of catalog files to be constructed.
+     if test -n "$LINGUAS"; then
+       for lang in $LINGUAS; do CATALOGS="$CATALOGS $lang$CATOBJEXT"; done
+     fi
+   fi
+
+   dnl The reference to <locale.h> in the installed <libintl.h> file
+   dnl must be resolved because we cannot expect the users of this
+   dnl to define HAVE_LOCALE_H.
+   if test $ac_cv_header_locale_h = yes; then
+     INCLUDE_LOCALE_H="#include <locale.h>"
+   else
+     INCLUDE_LOCALE_H="\
+/* The system does not provide the header <locale.h>.  Take care yourself.  */"
+   fi
+   AC_SUBST(INCLUDE_LOCALE_H)
+
+   dnl Determine which catalog format we have (if any is needed)
+   dnl For now we know about two different formats:
+   dnl   Linux libc-5 and the normal X/Open format
+   test -d intl || mkdir intl
+   if test "$CATOBJEXT" = ".cat"; then
+     AC_CHECK_HEADER(linux/version.h, msgformat=linux, msgformat=xopen)
+
+     dnl Transform the SED scripts while copying because some dumb SEDs
+     dnl cannot handle comments.
+     sed -e '/^#/d' $srcdir/intl/$msgformat-msg.sed > intl/po2msg.sed
+   fi
+   dnl po2tbl.sed is always needed.
+   sed -e '/^#.*[^\\]$/d' -e '/^#$/d' \
+     $srcdir/intl/po2tbl.sed.in > intl/po2tbl.sed
+
+   dnl In the intl/Makefile.in we have a special dependency which makes
+   dnl only sense for gettext.  We comment this out for non-gettext
+   dnl packages.
+   if test "$PACKAGE" = "gettext"; then
+     GT_NO="#NO#"
+     GT_YES=
+   else
+     GT_NO=
+     GT_YES="#YES#"
+   fi
+   AC_SUBST(GT_NO)
+   AC_SUBST(GT_YES)
+
+   dnl If the AC_CONFIG_AUX_DIR macro for autoconf is used we possibly
+   dnl find the mkinstalldirs script in another subdir but ($top_srcdir).
+   dnl Try to locate is.
+   MKINSTALLDIRS=
+   if test -n "$ac_aux_dir"; then
+     MKINSTALLDIRS="$ac_aux_dir/mkinstalldirs"
+   fi
+   if test -z "$MKINSTALLDIRS"; then
+     MKINSTALLDIRS="\$(top_srcdir)/mkinstalldirs"
+   fi
+   AC_SUBST(MKINSTALLDIRS)
+
+   dnl *** For now the libtool support in intl/Makefile is not for real.
+   l=
+   AC_SUBST(l)
+
+   dnl Generate list of files to be processed by xgettext which will
+   dnl be included in po/Makefile.
+   test -d po || mkdir po
+   if test "x$srcdir" != "x."; then
+     if test "x`echo $srcdir | sed 's@/.*@@'`" = "x"; then
+       posrcprefix="$srcdir/"
+     else
+       posrcprefix="../$srcdir/"
+     fi
+   else
+     posrcprefix="../"
+   fi
+   rm -f po/POTFILES
+   sed -e "/^#/d" -e "/^\$/d" -e "s,.*,	$posrcprefix& \\\\," -e "\$s/\(.*\) \\\\/\1/" \
+	< $srcdir/po/POTFILES.in > po/POTFILES
+  ])
+
+# Search path for a program which passes the given test.
+# Ulrich Drepper <drepper@cygnus.com>, 1996.
+#
+# This file can be copied and used freely without restrictions.  It can
+# be used in projects which are not available under the GNU Public License
+# but which still want to provide support for the GNU gettext functionality.
+# Please note that the actual code is *not* freely available.
+
+# serial 1
+
+dnl AM_PATH_PROG_WITH_TEST(VARIABLE, PROG-TO-CHECK-FOR,
+dnl   TEST-PERFORMED-ON-FOUND_PROGRAM [, VALUE-IF-NOT-FOUND [, PATH]])
+AC_DEFUN(AM_PATH_PROG_WITH_TEST,
+[# Extract the first word of "$2", so it can be a program name with args.
+set dummy $2; ac_word=[$]2
+AC_MSG_CHECKING([for $ac_word])
+AC_CACHE_VAL(ac_cv_path_$1,
+[case "[$]$1" in
+  /*)
+  ac_cv_path_$1="[$]$1" # Let the user override the test with a path.
+  ;;
+  *)
+  IFS="${IFS= 	}"; ac_save_ifs="$IFS"; IFS="${IFS}:"
+  for ac_dir in ifelse([$5], , $PATH, [$5]); do
+    test -z "$ac_dir" && ac_dir=.
+    if test -f $ac_dir/$ac_word; then
+      if [$3]; then
+	ac_cv_path_$1="$ac_dir/$ac_word"
+	break
+      fi
+    fi
+  done
+  IFS="$ac_save_ifs"
+dnl If no 4th arg is given, leave the cache variable unset,
+dnl so AC_PATH_PROGS will keep looking.
+ifelse([$4], , , [  test -z "[$]ac_cv_path_$1" && ac_cv_path_$1="$4"
+])dnl
+  ;;
+esac])dnl
+$1="$ac_cv_path_$1"
+if test -n "[$]$1"; then
+  AC_MSG_RESULT([$]$1)
+else
+  AC_MSG_RESULT(no)
+fi
+AC_SUBST($1)dnl
+])
+
+# Check whether LC_MESSAGES is available in <locale.h>.
+# Ulrich Drepper <drepper@cygnus.com>, 1995.
+#
+# This file can be copied and used freely without restrictions.  It can
+# be used in projects which are not available under the GNU Public License
+# but which still want to provide support for the GNU gettext functionality.
+# Please note that the actual code is *not* freely available.
+
+# serial 1
+
+AC_DEFUN(AM_LC_MESSAGES,
+  [if test $ac_cv_header_locale_h = yes; then
+    AC_CACHE_CHECK([for LC_MESSAGES], am_cv_val_LC_MESSAGES,
+      [AC_TRY_LINK([#include <locale.h>], [return LC_MESSAGES],
+       am_cv_val_LC_MESSAGES=yes, am_cv_val_LC_MESSAGES=no)])
+    if test $am_cv_val_LC_MESSAGES = yes; then
+      AC_DEFINE(HAVE_LC_MESSAGES)
+    fi
+  fi])
+
+# Configure paths for GLIB
+# Owen Taylor     97-11-3
+
+dnl AM_PATH_GLIB([MINIMUM-VERSION, [ACTION-IF-FOUND [, ACTION-IF-NOT-FOUND [, MODULES]]]])
+dnl Test for GLIB, and define GLIB_CFLAGS and GLIB_LIBS, if "gmodule" or 
+dnl gthread is specified in MODULES, pass to glib-config
+dnl
+AC_DEFUN(AM_PATH_GLIB,
+[dnl 
+dnl Get the cflags and libraries from the glib-config script
+dnl
+AC_ARG_WITH(glib-prefix,[  --with-glib-prefix=PFX   Prefix where GLIB is installed (optional)],
+            glib_config_prefix="$withval", glib_config_prefix="")
+AC_ARG_WITH(glib-exec-prefix,[  --with-glib-exec-prefix=PFX Exec prefix where GLIB is installed (optional)],
+            glib_config_exec_prefix="$withval", glib_config_exec_prefix="")
+AC_ARG_ENABLE(glibtest, [  --disable-glibtest       Do not try to compile and run a test GLIB program],
+		    , enable_glibtest=yes)
+
+  if test x$glib_config_exec_prefix != x ; then
+     glib_config_args="$glib_config_args --exec-prefix=$glib_config_exec_prefix"
+     if test x${GLIB_CONFIG+set} != xset ; then
+        GLIB_CONFIG=$glib_config_exec_prefix/bin/glib-config
+     fi
+  fi
+  if test x$glib_config_prefix != x ; then
+     glib_config_args="$glib_config_args --prefix=$glib_config_prefix"
+     if test x${GLIB_CONFIG+set} != xset ; then
+        GLIB_CONFIG=$glib_config_prefix/bin/glib-config
+     fi
+  fi
+
+  for module in . $4
+  do
+      case "$module" in
+         gmodule) 
+             glib_config_args="$glib_config_args gmodule"
+         ;;
+         gthread) 
+             glib_config_args="$glib_config_args gthread"
+         ;;
+      esac
+  done
+
+  AC_PATH_PROG(GLIB_CONFIG, glib-config, no)
+  min_glib_version=ifelse([$1], ,0.99.7,$1)
+  AC_MSG_CHECKING(for GLIB - version >= $min_glib_version)
+  no_glib=""
+  if test "$GLIB_CONFIG" = "no" ; then
+    no_glib=yes
+  else
+    GLIB_CFLAGS=`$GLIB_CONFIG $glib_config_args --cflags`
+    GLIB_LIBS=`$GLIB_CONFIG $glib_config_args --libs`
+    glib_config_major_version=`$GLIB_CONFIG $glib_config_args --version | \
+           sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\1/'`
+    glib_config_minor_version=`$GLIB_CONFIG $glib_config_args --version | \
+           sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\2/'`
+    glib_config_micro_version=`$GLIB_CONFIG $glib_config_args --version | \
+           sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\3/'`
+    if test "x$enable_glibtest" = "xyes" ; then
+      ac_save_CFLAGS="$CFLAGS"
+      ac_save_LIBS="$LIBS"
+      CFLAGS="$CFLAGS $GLIB_CFLAGS"
+      LIBS="$GLIB_LIBS $LIBS"
+dnl
+dnl Now check if the installed GLIB is sufficiently new. (Also sanity
+dnl checks the results of glib-config to some extent
+dnl
+      rm -f conf.glibtest
+      AC_TRY_RUN([
+#include <glib.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+int 
+main ()
+{
+  int major, minor, micro;
+  char *tmp_version;
+
+  system ("touch conf.glibtest");
+
+  /* HP/UX 9 (%@#!) writes to sscanf strings */
+  tmp_version = g_strdup("$min_glib_version");
+  if (sscanf(tmp_version, "%d.%d.%d", &major, &minor, &micro) != 3) {
+     printf("%s, bad version string\n", "$min_glib_version");
+     exit(1);
+   }
+
+  if ((glib_major_version != $glib_config_major_version) ||
+      (glib_minor_version != $glib_config_minor_version) ||
+      (glib_micro_version != $glib_config_micro_version))
+    {
+      printf("\n*** 'glib-config --version' returned %d.%d.%d, but GLIB (%d.%d.%d)\n", 
+             $glib_config_major_version, $glib_config_minor_version, $glib_config_micro_version,
+             glib_major_version, glib_minor_version, glib_micro_version);
+      printf ("*** was found! If glib-config was correct, then it is best\n");
+      printf ("*** to remove the old version of GLIB. You may also be able to fix the error\n");
+      printf("*** by modifying your LD_LIBRARY_PATH enviroment variable, or by editing\n");
+      printf("*** /etc/ld.so.conf. Make sure you have run ldconfig if that is\n");
+      printf("*** required on your system.\n");
+      printf("*** If glib-config was wrong, set the environment variable GLIB_CONFIG\n");
+      printf("*** to point to the correct copy of glib-config, and remove the file config.cache\n");
+      printf("*** before re-running configure\n");
+    } 
+  else if ((glib_major_version != GLIB_MAJOR_VERSION) ||
+	   (glib_minor_version != GLIB_MINOR_VERSION) ||
+           (glib_micro_version != GLIB_MICRO_VERSION))
+    {
+      printf("*** GLIB header files (version %d.%d.%d) do not match\n",
+	     GLIB_MAJOR_VERSION, GLIB_MINOR_VERSION, GLIB_MICRO_VERSION);
+      printf("*** library (version %d.%d.%d)\n",
+	     glib_major_version, glib_minor_version, glib_micro_version);
+    }
+  else
+    {
+      if ((glib_major_version > major) ||
+        ((glib_major_version == major) && (glib_minor_version > minor)) ||
+        ((glib_major_version == major) && (glib_minor_version == minor) && (glib_micro_version >= micro)))
+      {
+        return 0;
+       }
+     else
+      {
+        printf("\n*** An old version of GLIB (%d.%d.%d) was found.\n",
+               glib_major_version, glib_minor_version, glib_micro_version);
+        printf("*** You need a version of GLIB newer than %d.%d.%d. The latest version of\n",
+	       major, minor, micro);
+        printf("*** GLIB is always available from ftp://ftp.gtk.org.\n");
+        printf("***\n");
+        printf("*** If you have already installed a sufficiently new version, this error\n");
+        printf("*** probably means that the wrong copy of the glib-config shell script is\n");
+        printf("*** being found. The easiest way to fix this is to remove the old version\n");
+        printf("*** of GLIB, but you can also set the GLIB_CONFIG environment to point to the\n");
+        printf("*** correct copy of glib-config. (In this case, you will have to\n");
+        printf("*** modify your LD_LIBRARY_PATH enviroment variable, or edit /etc/ld.so.conf\n");
+        printf("*** so that the correct libraries are found at run-time))\n");
+      }
+    }
+  return 1;
+}
+],, no_glib=yes,[echo $ac_n "cross compiling; assumed OK... $ac_c"])
+       CFLAGS="$ac_save_CFLAGS"
+       LIBS="$ac_save_LIBS"
+     fi
+  fi
+  if test "x$no_glib" = x ; then
+     AC_MSG_RESULT(yes)
+     ifelse([$2], , :, [$2])     
+  else
+     AC_MSG_RESULT(no)
+     if test "$GLIB_CONFIG" = "no" ; then
+       echo "*** The glib-config script installed by GLIB could not be found"
+       echo "*** If GLIB was installed in PREFIX, make sure PREFIX/bin is in"
+       echo "*** your path, or set the GLIB_CONFIG environment variable to the"
+       echo "*** full path to glib-config."
+     else
+       if test -f conf.glibtest ; then
+        :
+       else
+          echo "*** Could not run GLIB test program, checking why..."
+          CFLAGS="$CFLAGS $GLIB_CFLAGS"
+          LIBS="$LIBS $GLIB_LIBS"
+          AC_TRY_LINK([
+#include <glib.h>
+#include <stdio.h>
+],      [ return ((glib_major_version) || (glib_minor_version) || (glib_micro_version)); ],
+        [ echo "*** The test program compiled, but did not run. This usually means"
+          echo "*** that the run-time linker is not finding GLIB or finding the wrong"
+          echo "*** version of GLIB. If it is not finding GLIB, you'll need to set your"
+          echo "*** LD_LIBRARY_PATH environment variable, or edit /etc/ld.so.conf to point"
+          echo "*** to the installed location  Also, make sure you have run ldconfig if that"
+          echo "*** is required on your system"
+	  echo "***"
+          echo "*** If you have an old version installed, it is best to remove it, although"
+          echo "*** you may also be able to get things to work by modifying LD_LIBRARY_PATH"
+          echo "***"
+          echo "*** If you have a RedHat 5.0 system, you should remove the GTK package that"
+          echo "*** came with the system with the command"
+          echo "***"
+          echo "***    rpm --erase --nodeps gtk gtk-devel" ],
+        [ echo "*** The test program failed to compile or link. See the file config.log for the"
+          echo "*** exact error that occured. This usually means GLIB was incorrectly installed"
+          echo "*** or that you have moved GLIB since it was installed. In the latter case, you"
+          echo "*** may want to edit the glib-config script: $GLIB_CONFIG" ])
+          CFLAGS="$ac_save_CFLAGS"
+          LIBS="$ac_save_LIBS"
+       fi
+     fi
+     GLIB_CFLAGS=""
+     GLIB_LIBS=""
+     ifelse([$3], , :, [$3])
+  fi
+  AC_SUBST(GLIB_CFLAGS)
+  AC_SUBST(GLIB_LIBS)
+  rm -f conf.glibtest
+])
+
diff --git a/autogen.sh b/autogen.sh
new file mode 100755
index 0000000..bda8fda
--- /dev/null
+++ b/autogen.sh
@@ -0,0 +1,91 @@
+#!/bin/sh
+# Run this to generate all the initial makefiles, etc.
+
+srcdir=`dirname $0`
+test -z "$srcdir" && srcdir=.
+
+ORIGDIR=`pwd`
+cd $srcdir
+PROJECT=mdk
+TEST_TYPE=-d
+FILE=mixlib
+
+DIE=0
+
+grep "^AM_GNU_GETTEXT" $srcdir/configure.in >/dev/null && {
+  (gettext --version) < /dev/null > /dev/null 2>&1 || {
+    echo
+    echo "**Error**: You must have \`gettext' installed to compile $PROJECT."
+    echo "Download the appropriate package for your distribution,"
+    echo "or get ftp://alpha.gnu.org/gnu/gettext-0.10.35.tar.gz"
+    echo "(or a newer version if it is available)"
+    DIE=1
+  }
+}
+
+(autoconf --version) < /dev/null > /dev/null 2>&1 || {
+	echo
+	echo "You must have autoconf installed to compile $PROJECT."
+	echo "Download the appropriate package for your distribution,"
+	echo "or get the source tarball at ftp://ftp.gnu.org/pub/gnu/"
+	DIE=1
+}
+
+(automake --version) < /dev/null > /dev/null 2>&1 || {
+	echo
+	echo "You must have automake installed to compile $PROJECT."
+	echo "Get ftp://sourceware.cygnus.com/pub/automake/automake-1.4.tar.gz"
+	echo "(or a newer version if it is available)"
+	DIE=1
+	NO_AUTOMAKE=yes
+}
+
+# if no automake, don't bother testing for aclocal
+test -n "$NO_AUTOMAKE" || (aclocal --version) < /dev/null > /dev/null 2>&1 || {
+  echo
+  echo "**Error**: Missing \`aclocal'.  The version of \`automake'"
+  echo "installed doesn't appear recent enough."
+  echo "Get ftp://ftp.gnu.org/pub/gnu/automake-1.3.tar.gz"
+  echo "(or a newer version if it is available)"
+  DIE=1
+}
+
+
+if test "$DIE" -eq 1; then
+	exit 1
+fi
+
+test $TEST_TYPE $FILE || {
+	echo "You must run this script in the top-level $PROJECT directory"
+	exit 1
+}
+
+if test -z "$*"; then
+	echo "I am going to run ./configure with no arguments - if you wish "
+        echo "to pass any to it, please specify them on the $0 command line."
+fi
+
+case $CC in
+*xlc | *xlc\ * | *lcc | *lcc\ *) am_opt=--include-deps;;
+esac
+
+echo "Running gettextize...  Ignore non-fatal messages."
+echo "no" | gettextize --force
+
+echo "Running aclocal ..."
+aclocal $ACLOCAL_FLAGS
+
+# optionally feature autoheader
+(autoheader --version)  < /dev/null > /dev/null 2>&1 && autoheader
+
+echo "Running automake --add-missing --gnu $am_opt ..."
+automake -a --gnu $am_opt
+
+echo "Running autoconf ..."
+autoconf
+cd $ORIGDIR
+
+$srcdir/configure --enable-maintainer-mode "$@"
+
+echo 
+echo "Now type 'make' to compile $PROJECT."
diff --git a/configure.in b/configure.in
new file mode 100644
index 0000000..d2386d0
--- /dev/null
+++ b/configure.in
@@ -0,0 +1,56 @@
+# Copyright (C) 2000 Jose Antonio Ortega Ruiz <jaortega@retemail.es>
+#  
+# This file is free software; as a special exception the author gives
+# unlimited permission to copy and/or distribute it, with or without 
+# modifications, as long as this notice is preserved.
+# 
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+AC_INIT(mixlib/mix.h)
+AM_CONFIG_HEADER(config.h)
+AM_INIT_AUTOMAKE(mdk,0.1)
+
+AM_MAINTAINER_MODE
+
+AC_ISC_POSIX
+AC_PROG_CC
+AM_PROG_CC_STDC
+AC_HEADER_STDC
+
+AM_PROG_LEX
+AC_PROG_RANLIB
+
+dnl i18n stuff
+ALL_LINGUAS="ca"
+AM_GNU_GETTEXT
+
+test "x$prefix" = xNONE && prefix=$ac_default_prefix
+
+AC_DEFINE_UNQUOTED(LOCALEDIR, "${prefix}/share/locale")
+
+dnl Check for readline and history
+AC_CHECK_LIB(readline, readline, , AC_MSG_ERROR(Cannot find GNU readline lib))
+AC_CHECK_LIB(history, add_history, , AC_MSG_ERROR(Cannot GNU history lib))
+
+
+dnl Check for glib
+AM_PATH_GLIB(1.2.0,
+		[LIBS="$LIBS $GLIB_LIBS" CFLAGS="$CFLAGS $GLIB_CFLAGS"],
+		AC_MSG_ERROR(Cannot find GLIB), "gmodule" )
+
+CFLAGS="$CFLAGS -Wall"
+AC_SUBST(CFLAGS)
+
+AC_OUTPUT( 
+Makefile 
+doc/Makefile 
+doc/html/Makefile 
+mixlib/Makefile 
+mixlib/testsuite/Makefile 
+mixutils/Makefile 
+intl/Makefile 
+samples/Makefile
+po/Makefile.in 
+)
diff --git a/doc/.cvsignore b/doc/.cvsignore
new file mode 100644
index 0000000..26676b1
--- /dev/null
+++ b/doc/.cvsignore
@@ -0,0 +1,8 @@
+Makefile
+Makefile.in
+mdk.html
+mdk.info
+mdk.info-1
+mdk.info-2
+stamp-vti
+version.texi
diff --git a/doc/Makefile.am b/doc/Makefile.am
new file mode 100644
index 0000000..754ab11
--- /dev/null
+++ b/doc/Makefile.am
@@ -0,0 +1,15 @@
+## Process this file with automake to produce Makefile.in
+
+# Copyright (C) 2000 jose antonio ortega ruiz <jaortega@retemail.es>
+#  
+# This file is free software; as a special exception the author gives
+# unlimited permission to copy and/or distribute it, with or without 
+# modifications, as long as this notice is preserved.
+# 
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+SUBDIRS = html
+info_TEXINFOS = mdk.texi
+mdk_TEXINFOS = gpl.texi
diff --git a/doc/gpl.texi b/doc/gpl.texi
new file mode 100644
index 0000000..5b0da1a
--- /dev/null
+++ b/doc/gpl.texi
@@ -0,0 +1,396 @@
+@setfilename gpl.info
+
+@unnumbered GNU GENERAL PUBLIC LICENSE
+@center Version 2, June 1991
+
+@display
+Copyright @copyright{} 1989, 1991 Free Software Foundation, Inc.
+675 Mass Ave, Cambridge, MA 02139, USA
+
+Everyone is permitted to copy and distribute verbatim copies
+of this license document, but changing it is not allowed.
+@end display
+
+@unnumberedsec Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software---to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+@iftex
+@unnumberedsec TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+@end iftex
+@ifinfo
+@center TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+@end ifinfo
+
+@enumerate
+@item
+This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The ``Program'', below,
+refers to any such program or work, and a ``work based on the Program''
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term ``modification''.)  Each licensee is addressed as ``you''.
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+@item
+You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+@item
+You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+@enumerate a
+@item
+You must cause the modified files to carry prominent notices
+stating that you changed the files and the date of any change.
+
+@item
+You must cause any work that you distribute or publish, that in
+whole or in part contains or is derived from the Program or any
+part thereof, to be licensed as a whole at no charge to all third
+parties under the terms of this License.
+
+@item
+If the modified program normally reads commands interactively
+when run, you must cause it, when started running for such
+interactive use in the most ordinary way, to print or display an
+announcement including an appropriate copyright notice and a
+notice that there is no warranty (or else, saying that you provide
+a warranty) and that users may redistribute the program under
+these conditions, and telling the user how to view a copy of this
+License.  (Exception: if the Program itself is interactive but
+does not normally print such an announcement, your work based on
+the Program is not required to print an announcement.)
+@end enumerate
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+@item
+You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+@enumerate a
+@item
+Accompany it with the complete corresponding machine-readable
+source code, which must be distributed under the terms of Sections
+1 and 2 above on a medium customarily used for software interchange; or,
+
+@item
+Accompany it with a written offer, valid for at least three
+years, to give any third party, for a charge no more than your
+cost of physically performing source distribution, a complete
+machine-readable copy of the corresponding source code, to be
+distributed under the terms of Sections 1 and 2 above on a medium
+customarily used for software interchange; or,
+
+@item
+Accompany it with the information you received as to the offer
+to distribute corresponding source code.  (This alternative is
+allowed only for noncommercial distribution and only if you
+received the program in object code or executable form with such
+an offer, in accord with Subsection b above.)
+@end enumerate
+
+The source code for a work means the preferred form of the work for
+making modifications to it.  For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable.  However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+@item
+You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+@item
+You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+@item
+Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+@item
+If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+@item
+If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+@item
+The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and ``any
+later version'', you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+@item
+If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+@iftex
+@heading NO WARRANTY
+@end iftex
+@ifinfo
+@center NO WARRANTY
+@end ifinfo
+
+@item
+BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM ``AS IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+@item
+IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+@end enumerate
+
+@iftex
+@heading END OF TERMS AND CONDITIONS
+@end iftex
+@ifinfo
+@center END OF TERMS AND CONDITIONS
+@end ifinfo
+
+@page
+@unnumberedsec How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the ``copyright'' line and a pointer to where the full notice is found.
+
+@smallexample
+@var{one line to give the program's name and an idea of what it does.}
+Copyright (C) 19@var{yy}  @var{name of author}
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+@end smallexample
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+@smallexample
+Gnomovision version 69, Copyright (C) 19@var{yy} @var{name of author}
+Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
+type `show w'.  This is free software, and you are welcome
+to redistribute it under certain conditions; type `show c' 
+for details.
+@end smallexample
+
+The hypothetical commands @samp{show w} and @samp{show c} should show
+the appropriate parts of the General Public License.  Of course, the
+commands you use may be called something other than @samp{show w} and
+@samp{show c}; they could even be mouse-clicks or menu items---whatever
+suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a ``copyright disclaimer'' for the program, if
+necessary.  Here is a sample; alter the names:
+
+@smallexample
+@group
+Yoyodyne, Inc., hereby disclaims all copyright
+interest in the program `Gnomovision'
+(which makes passes at compilers) written 
+by James Hacker.
+
+@var{signature of Ty Coon}, 1 April 1989
+Ty Coon, President of Vice
+@end group
+@end smallexample
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.
diff --git a/doc/html/.cvsignore b/doc/html/.cvsignore
new file mode 100644
index 0000000..b44cc40
--- /dev/null
+++ b/doc/html/.cvsignore
@@ -0,0 +1,16 @@
+Makefile
+Makefile.in
+doc.html
+mdk.html
+mdk_1.html
+mdk_2.html
+mdk_3.html
+mdk_4.html
+mdk_5.html
+mdk_6.html
+mdk_7.html
+mdk_8.html
+mdk_abt.html
+mdk_fot.html
+mdk_ovr.html
+mdk_toc.html
diff --git a/doc/html/Makefile.am b/doc/html/Makefile.am
new file mode 100644
index 0000000..ecd8550
--- /dev/null
+++ b/doc/html/Makefile.am
@@ -0,0 +1,14 @@
+## Process this file with automake to produce Makefile.in
+
+# Copyright (C) 2000 Jose Antonio Ortega Ruiz <jaortega@retemail.es>
+#  
+# This file is free software; as a special exception the author gives
+# unlimited permission to copy and/or distribute it, with or without 
+# modifications, as long as this notice is preserved.
+# 
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+EXTRA_DIST = index.html download.html
+
diff --git a/doc/html/download.html b/doc/html/download.html
new file mode 100644
index 0000000..0749404
--- /dev/null
+++ b/doc/html/download.html
@@ -0,0 +1,105 @@
+<!-- -*-html-*- -->
+<html>
+
+  <head>
+    <title>MDK download</title>
+  </head>
+
+  <body bgcolor="white" link="#ff0000" vlink="#a00000">
+    <a  name="top"></a>
+    <table  cellspacing="0" cellpadding="5" border="0" align="center">
+      <tr>
+        <td width="100" bgcolor="#696969">&nbsp;</td>
+        <td bgcolor="#696969" width="600" align="center"> 
+           <font color="white"><b>MDK download</b></font>
+	</td>
+	<td bgcolor="#696969" width="10">&nbsp;</td>
+      </tr>
+      <tr>
+        <td colspan="2">&nbsp;</td>
+	<td bgcolor="#696969" >&nbsp;</td>
+      </tr>
+      <tr>
+        <td  bgcolor="#909090" valign="top">
+	  <br>
+	  <a href="index.html">MDK home</a><br>
+	  <a href="mdk.html">Documentation</a><br>
+	  <a href="http://sourceforge.net/projects/mdk">
+	    MDK at SourceForge</a><br>
+	  <a href="http://cvs.sourceforge.net/cgi-bin/cvsweb.cgi/?cvsroot=mdk">
+	    CVS repository</a><br><br>
+	  <p align="center">Thanks to<br>
+	  <A href="http://sourceforge.net"> 
+          <IMG src="http://sourceforge.net/sflogo.php?group_id=13897&type=1"
+	       width="88" height="31" border="0"
+               alt="SourceForge Logo"> </A> 
+	</td>
+        <td >
+	  <p align="right"><font color="#000069" size="+1">
+           Download
+	  </font></p>
+	  <p>The latest version (0.1) source tarball is available for
+	  download <a href="http://sourceforge.net/projects/mdk">here.</a></p>
+	  <p>A tarball containing the HTML documentation is available
+          <a href="mdk-doc.tar.gz">here.</a></p>
+	  <p align="right"><font color="#000069" size="+1">
+           <a name="reqs">Requirements</a>
+	  </font></p>
+	  MDK is written in ANSI C and uses the following libraries:
+	  <ul>
+	    <li>GNU readline and history
+	    <li><a href="http://www.gnu.org/software/flex/flex.html">
+	         GNU Flex</a>, version 2.3 or latter
+            <li><a href="http://www.gtk.org">glib</a>, version 1.2.0 or latter
+	  </ul>
+	  These libraries are fairly common in any GNU/Linux distribution
+	  (MDK is developed on a <a href="www.debian.org">Debian 2.3</a>
+          box). Although I haven't tested it, MDK should be also installable
+	  on BSD operating systems such as FreeBSD if the above libraries
+          are installed. Please, 
+	  <a href="mailto:jaortega@acm.org">drop me</a> a line if you install
+	  MDK, and I'll add your platform to the list of supported ones.
+	  <p align="right"><font color="#000069" size="+1">
+           Installation
+	  </font></p>
+	  MDK uses autoconf/automake, so that compilation and installation
+	  should follow the typical uncompress, configure, make, install cycle.
+	  First, uncompress the source tarball using:
+	  <pre>
+    tar xvfz mdk-latest.tar.gz
+          </pre>
+	  This will create a folder named mdk-X.Y (where X.Y stands for
+	  the version you downloaded, e.g., 0.1). To build the MDK tools,
+	  enter this folder and type
+	  <pre>
+    ./configure
+    make
+          </pre>
+	  Finally, to install the binaries and documentation, type, as root
+          <pre>
+    make install
+          </pre>
+	  See the file named INSTALL in the source folder for fine tuning 
+          of build and installation options.
+	  <p align="right">
+	   Contact the <a href="mailto:jaortega@acm.org">author.</a>
+	  </p>
+        </td>
+	<td bgcolor="#696969" >&nbsp;</td>
+      </tr>
+      <tr>
+        <td bgcolor="#909090">&nbsp;</td>
+        <td colspan="2">&nbsp;</td>
+      </tr>
+      <tr>
+        <td bgcolor="#909090">&nbsp;</td>
+        <td colspan="2" bgcolor="#909090" align="right">
+	  &nbsp;
+	</td>
+      </tr>
+    </table>
+    
+  </body>
+</html>
+
+
diff --git a/doc/html/index.html b/doc/html/index.html
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+<!-- -*-html-*- -->
+<html>
+
+  <head>
+    <title>MIX Development Kit</title>
+  </head>
+
+  <body bgcolor="white" link="#ff0000" vlink="#a00000">
+    <a  name="top"></a>
+    <table  cellspacing="0" cellpadding="5" border="0" align="center">
+      <tr>
+        <td width="100" bgcolor="#696969">&nbsp;</td>
+        <td bgcolor="#696969" width="600" align="center"> 
+           <font color="white"><b>MDK, the MIX development kit</b></font>
+	</td>
+	<td bgcolor="#696969" width="10">&nbsp;</td>
+      </tr>
+      <tr>
+        <td colspan="2">&nbsp;</td>
+	<td bgcolor="#696969" >&nbsp;</td>
+      </tr>
+      <tr>
+        <td  bgcolor="#909090" valign="top">
+	  <br>
+	  <a href="download.html">Download</a><br>
+	  <a href="mdk.html">Documentation</a><br>
+	  <a href="http://sourceforge.net/projects/mdk">
+	    MDK at SourceForge</a><br>
+	  <a href="http://cvs.sourceforge.net/cgi-bin/cvsweb.cgi/?cvsroot=mdk">
+	    CVS repository</a><br><br>
+	  <p align="center">Thanks to<br>
+	  <A href="http://sourceforge.net"> 
+          <IMG src="http://sourceforge.net/sflogo.php?group_id=13897&type=1"
+	       width="88" height="31" border="0"
+               alt="SourceForge Logo"> </A> 
+	</td>
+        <td >
+	  <p align="right"><font color="#000069" size="+1">
+           What is the MIX?
+	  </font></p>
+	  <b>MIX</b> is Donald Knuth's mythical computer as described
+	  in his monumental work <a
+	  href="http://Sunburn.Stanford.EDU/~knuth/taocp.html"> The
+	  Art Of Computer Programming</a>. As any of its real
+	  counterparts, the MIX features registers, memory cells, an
+	  overflow toggle, comparison flags, input-output devices, and
+	  a set of binary instructions executable by its virtual
+	  CPU. You can programme the MIX using an assembly language
+	  called <b>MIXAL</b>, the MIX Assembly Language.  <p> So,
+	  what's the use of learning MIXAL? Well, if you're interested
+	  in programming, please buy, borrow or steal a copy of TAOCP,
+	  and you'll see the use.  
+	  &nbsp;<br>&nbsp;<br>
+	  <p align="right"><font color="#000069" size="+1">
+            What is the MDK?
+	  </font></p> 
+	  The <b>M</b>IX <b>D</b>evelopment <b>K</b>it offers an emulation of
+	  <b>MIX</b> and <b>MIXAL</b>. The <a href="download.html">
+	  current version</a> of MDK includes two applications:
+	  <ul>
+	    <li><b><i>mixasm</i></b> A MIXAL compiler, which
+	    translates your source files into binary ones, executable
+	    by the MIX virtual machine.
+            <li><b><i>mixvm</i></b> A MIX virtual machine which is
+	    able to run and debug compiled MIXAL programs, using a
+	    command line interface with readline's line editting
+	    capabilities.
+	  </ul>
+	  Using the MDK tools, you'll be able to
+	  <ul>
+	    <li>write, compile and execute MIXAL programs,
+	    <li>set breakpoints and run your programs step by step,
+	    <li>inspect and modify the MIX registers, flags and memory
+	    contents at any step,
+	    <li>simulate MIX input-output devices using the standard
+	    output and your file system.
+	  </ul>
+	  See the MDK <a href="mdk.html">user's manual</a> for a complete
+	  description of the toolkit.
+	  The MDK utils will run on any GNU/Linux box (see
+	  <a href="download.html#reqs">requirements</a>) and, of course, are
+	  <a href="http://www.gnu.org/copyleft/gpl.html">free software</a>.
+	  <p align="right">
+	   Contact the <a href="mailto:jaortega@acm.org">author.</a>
+	  </p>
+        </td>
+	<td bgcolor="#696969" >&nbsp;</td>
+      </tr>
+      <tr>
+        <td bgcolor="#909090">&nbsp;</td>
+        <td colspan="2">&nbsp;</td>
+      </tr>
+      <tr>
+        <td bgcolor="#909090">&nbsp;</td>
+        <td colspan="2" bgcolor="#909090" align="right">
+	  &nbsp;
+	</td>
+      </tr>
+    </table>
+    
+  </body>
+</html>
+
+
diff --git a/doc/mdk.texi b/doc/mdk.texi
new file mode 100644
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--- /dev/null
+++ b/doc/mdk.texi
@@ -0,0 +1,1763 @@
+\input texinfo @c -*-texinfo-*-
+@c %**start of header
+@setfilename mdk.info
+@settitle MIX Development Kit (mdk)
+@finalout
+@setchapternewpage odd
+@c %**end of header
+
+@include version.texi
+@set JAO Jos@'e Antonio Ortega Ruiz
+@footnotestyle separate
+
+@ifinfo
+This file documents the the @sc{mdk} utilities for developing
+programs using Donald Knuth's MIX language.
+
+Copyright (C) 2000 @value{JAO}
+
+Permission is granted to make and distribute verbatim copies of
+this manual provided the copyright notice and this permission notice
+are preserved on all copies.
+
+@ignore
+Permission is granted to process this file through TeX and print the
+results, provided the printed document carries copying permission
+notice identical to this one except for the removal of this paragraph
+(this paragraph not being relevant to the printed manual).
+
+@end ignore
+Permission is granted to copy and distribute modified versions of this
+manual under the conditions for verbatim copying, provided also that the
+sections entitled ``Copying'' and ``GNU General Public License'' are
+included exactly as in the original, and provided that the entire
+resulting derived work is distributed under the terms of a permission
+notice identical to this one.
+
+Permission is granted to copy and distribute translations of this manual
+into another language, under the above conditions for modified versions,
+except that this permission notice may be stated in a translation
+approved by the Free Software Foundation.
+@end ifinfo
+
+@titlepage
+@title MDK
+@subtitle MIX Development Kit
+@subtitle Edition @value{EDITION}, for @sc{mdk} Version @value{VERSION}
+@subtitle @value{UPDATED}
+@author by @value{JAO}
+
+@page
+@vskip 0pt plus 1filll
+Copyright @copyright{} 2000 @value{JAO}
+
+Permission is granted to make and distribute verbatim copies of
+this manual provided the copyright notice and this permission notice
+are preserved on all copies.
+
+Permission is granted to copy and distribute modified versions of this
+manual under the conditions for verbatim copying, provided also that the
+sections entitled ``Copying'' and ``GNU General Public License'' are
+included exactly as in the original, and provided that the entire
+resulting derived work is distributed under the terms of a permission
+notice identical to this one.
+
+Permission is granted to copy and distribute translations of this manual
+into another language, under the above conditions for modified versions,
+except that this permission notice may be stated in a translation
+approved by the Free Software Foundation.
+@end titlepage
+
+@node Top, Introduction, (dir), (dir)
+
+@ifinfo
+This file documents the @sc{mdk} utilities to develop programs
+using Donald Knuth's MIXAL language.  MIXAL is an assembler-like
+language for writing programs for the (virtual) MIX computer. They are
+described in the first volume of @cite{The Art of Computer Programming}
+by D. Knuth (Addison Wesley, 1997), and used throughout the (up to now)
+three published volumes.
+
+@sc{mdk} was written by @value{JAO} and is released under the GNU
+General Public license (@pxref{Copying}), so that users are free to share
+and change it.
+
+@end ifinfo
+
+@menu
+* Introduction::                
+* MIX and MIXAL overview::      Quick tutorial of Knuth's MIX computer.
+* Getting started::             Basic usage of the @sc{mdk} tools.
+* mixvm::                       Invoking the MIX virtual machine.
+* mixasm::                      Invoking the MIXAL assembler.
+* Copying::                     @sc{mdk} licensing terms.
+* Problems::                    Reporting bugs.
+* Concept Index::               Index of concepts.
+
+@detailmenu
+ --- The Detailed Node Listing ---
+
+MIX and MIXAL overview
+
+* The MIX computer::            Architecture and instruction set 
+                                of the MIX computer.
+* MIXAL::                       The MIX assembly language.
+
+The MIX computer
+
+* MIX architecture::            
+* MIX instruction set::         
+
+MIX instruction set
+
+* Loading operators::           
+* Storing operators::           
+* Arithmetic operators::        
+* Address transfer operators::  
+* Comparison operators::        
+* Jump operators::              
+* Miscellaneous operators::     
+* Input-output operators::      
+* Conversion operators::        
+
+MIXAL
+
+* Instructions::                
+* Comments::                    
+* Expressions::                 
+* Local symbols::               
+* Miscellaneous::               
+
+Getting started
+
+* Writing a source file::       A sample MIXAL source file.
+* Compiling::                   Using @code{mixasm} to compile source
+                                files into binary format.
+* Running the program::         Running and debugging your program.
+
+Running the program
+
+* Non-interactive mode::        Running your programs non-interactively.
+* Interactive mode::            Running programs interactively.
+* Debugging::                   Commands for debugging your programs.
+
+@code{mixvm}, the MIX computer simulator
+
+* Invocation::                  Options when invoking @code{mixvm}.
+* Commands::                    Commands available in interactive mode.
+* Devices::                     MIX block devices implementation.
+
+@code{mixasm}, the MIXAL assembler
+
+* Invoking @code{mixasm}::      @code{mixasm} options
+
+@end detailmenu
+@end menu
+
+@node Introduction, MIX and MIXAL overview, Top, Top
+@comment  node-name,  next,  previous,  up
+@unnumbered Introduction
+@cindex Introduction
+
+In his book series @cite{The Art of Computer Programming} (published by
+Addison Wesley), D. Knuth uses an imaginary computer, the MIX, and its
+associated machine-code and assembly languages to ilustrate the
+concepts and algorithms as they are presented. 
+
+The MIX's architecture is a simplified version of those found in real
+CSIC CPUs, and the MIX assembly language provides a set of primitives
+that will be very familiar to any person with a minimum experience in
+assembly programming. The MIX/MIXAL definition is powerful and complete
+enough to provide a virtual development platform for writing quite
+complex programs, and close enough to real computers to be worth using
+when learning programming techniques. At any rate, if you want to read
+and learn from Knuth excellent books on computer programming, a MIX
+development environment would come in handy.
+
+The @sc{mdk} package aims at providing such virtual development
+environment on a GNU box. Thus, @sc{mdk} offers you a set of utilities
+to simulate the MIX computer and to write, compile, run and debug MIXAL
+programs. As of version @value{VERSION}, @sc{mdk} includes
+the following programs:
+
+@table @code
+@item mixvm
+MIX virtual machine. Emulation of the MIX computer.
+@item mixasm
+MIXAL assembler. Assembler which translates MIXAL source files into
+programs that can be run (and debugged) by @code{mixvm}.
+@end table 
+
+@code{mixvm} implements a simulator of the MIX computer, giving you a
+virtual machine for executing and debugging MIX programs. These binary
+programs could be written by hand, but it is easier to produce them
+compiling MIXAL source files, using the MIXAL assembler @code{mixasm}.
+
+This manual gives you a brief survey of MIX and MIXAL, and a thorough
+description of the use of the @sc{mdk} utilities.
+
+
+
+@node MIX and MIXAL overview, Getting started, Introduction, Top
+@comment  node-name,  next,  previous,  up
+@chapter MIX and MIXAL overview
+@cindex MIX
+@cindex MIXAL
+
+In the book series @cite{The Art of Computer Programming}, by D. Knuth,
+a virtual computer, the MIX, is used by the author, together with the
+set of binary instructions that the virtual CPU accepts, in the example
+programs and exercises. Like any other real computer, there is a
+symbolic assembler language that can be used to program the MIX: the MIX
+assembly language, or MIXAL for short. The MIX computer architecture and
+the MIXAL language are defined in volume 1 of the series,
+@cite{Fundamental Algorithms}. In the following subsections you will
+find a brief survey of these topics, which is not meant to replace the
+precise description given in the book (if you are interested in using
+the @sc{mdk} utilities, most probably the reason is that you have access
+to a copy of TAOCP), but to serve as a quick reminder of key points and
+nomenclature used in the rest of this manual.
+
+@menu
+* The MIX computer::            Architecture and instruction set 
+                                of the MIX computer.
+* MIXAL::                       The MIX assembly language.
+@end menu
+
+@node The MIX computer, MIXAL, MIX and MIXAL overview, MIX and MIXAL overview
+@comment  node-name,  next,  previous,  up
+@section The MIX computer
+
+In this section, you will find a brief description of the MIX computer,
+its components and instruction set.
+
+@menu
+* MIX architecture::            
+* MIX instruction set::         
+@end menu
+
+@node MIX architecture, MIX instruction set, The MIX computer, The MIX computer
+@comment  node-name,  next,  previous,  up
+@subsection MIX architecture
+@cindex byte
+@cindex MIX byte
+@cindex word
+@cindex MIX word
+@cindex MIX architecture
+@cindex MIX computer
+@cindex register
+@cindex MIX register
+@cindex field specification
+@cindex fspec
+@cindex instruction
+@cindex MIX instruction
+@cindex address
+@cindex memory cell
+@cindex cell
+@cindex memory
+@cindex index
+
+The basic information storage unit in the MIX computer is the
+@dfn{byte}, which stores positive values in the range 0-63 . Note that a
+MIX byte can be then represented as 6 bits, instead of the common 8 bits
+for a @emph{regular} byte. Unless otherwise stated, we shall use the
+word @dfn{byte} to refer to a MIX 6-bit byte.
+
+A MIX @dfn{word} is defined as a set of 5 bytes plus a sign. The bytes
+within a word are numbered for 1 to 5, being byte number one the most
+significant one. The sign is denoted by index 0. Graphically,
+
+@example
+ -----------------------------------------------
+|   0   |   1   |   2   |   3   |   4   |   5   |
+ -----------------------------------------------
+|  +/-  | byte  | byte  | byte  | byte  | byte  |     
+ -----------------------------------------------
+@end example
+
+You can refer to subfields within a word using a
+@dfn{field specification} or @dfn{fspec} of the form @samp{(L:R)}, where
+@samp{L} denotes the first byte and @samp{R} the last byte of the
+subfield. When @samp{L} is zero, the subfield includes the word's
+sign. An fspec can be also represented as a single value @samp{F}, given
+by @code{F = 8*L + R}.
+
+The MIX computer stores information in @dfn{registers}, that can store
+either a word or two bytes and sign (see below), and @dfn{memory cells},
+each one containing a word. Specifically, the MIX computer has 4000
+memory cells with addresses 0 to 3999 (i.e., two bytes are enough to
+address a memory cell) and the following registers:
+
+@table @samp
+@item rA
+A register. General purpose register holding a word. Usually its
+contents serves as operator for arithmetic and storing instructions.
+@item rX
+X register. General purpose register holding a word. Often it acts as an
+extension or a replacement of @samp{rA}.
+@item rJ
+J (jump) register. This register stores positive two-byte values,
+usually representing a jump address.
+@item rI[1-6]
+Index registers. These six registers can store a signed two-byte
+value. Their contents is used as indexing values for the computation of
+an effective memory address.
+@end table
+
+@cindex @sc{ov}
+@cindex @sc{cm}
+@cindex @samp{Un}
+@cindex overflow toggle
+@cindex comparison indicator
+@cindex input-output devices
+@noindent
+In addition, the MIX computer contains:
+
+@itemize @minus
+@item
+An @dfn{overflow toggle} (a single bit with values @dfn{on} or
+@dfn{off}). In this manual, this toggle is denoted @sc{ov}.
+@item
+A @dfn{comparison indicator} (having three values: @dfn{EQUAL},
+@dfn{GREATER} or @dfn{LESS}). In this manual, this indicator is denoted
+@sc{cm}.
+@item
+Input-output devices. Each device is labelled as @samp{Un}, where
+@samp{n} runs from 0 to 19@footnote{@samp{U0-7} are magnetic tape units,
+@samp{U8-15} are disks and drums, @samp{U16} is a card reader,
+@samp{U17} is a card writer, @samp{U18} is a line printer and
+@samp{U19}, a paper tape.}.
+@end itemize
+
+MIX @dfn{instructions} are codified as words with the following subfield
+structure:
+
+@multitable @columnfractions .15 .20 .65
+@item @emph{Subfield} @tab @emph{fspec} @tab @emph{Description}
+
+@item ADDRESS @tab (0:2)
+@tab The first two bytes plus sign are the @dfn{address} field. Combined
+with the INDEX field, denotes the memory address to be used by the
+instruction.
+@item INDEX @tab (3:3) @tab
+The third byte is the @dfn{index}, normally used for indexing the
+address@footnote{The actual memory address the instruction refers to, is
+obtained by adding to ADDRESS the value of the @samp{rI} register
+denoted by INDEX.}.
+@item MOD @tab (4:4) @tab
+Byte four is used either as an operation code modifier or as a field
+specification.
+@item OPCODE @tab (5:5) @tab
+The last (least significant) byte in the word denotes the operation
+code.
+@end multitable
+
+@noindent
+or, graphically,
+
+@example
+ ------------------------------------------------
+|   0   |   1   |   2   |   3   |   4   |   5    |
+ ------------------------------------------------
+|        ADDRESS        | INDEX |  MOD  | OPCODE |     
+ ------------------------------------------------
+@end example
+
+The MIX computer understands a quite complete set of instructions
+commonly found in real computers, including arithmetic, logical,
+storing, comparison and jump instructions. We refer the reader to
+D. Knuth's TAOCP (volume 1, section 1.3.1) for a complete description of
+these instructions. @xref{MIX instruction set}, gives a quick synopsis
+of the available instructions.
+
+@node MIX instruction set,  , MIX architecture, The MIX computer
+@comment  node-name,  next,  previous,  up
+@subsection MIX instruction set
+@cindex instruction set
+
+The following subsections summarize the instruction set of the MIX
+computer. In this description @samp{M} stands for
+the memory address obtained after indexing the ADDRESS subfield of the
+instruction (using its INDEX byte), and @samp{V} is the contents of the
+subfield indicated by MOD of the memory cell with address @samp{M}.
+
+@menu
+* Loading operators::           
+* Storing operators::           
+* Arithmetic operators::        
+* Address transfer operators::  
+* Comparison operators::        
+* Jump operators::              
+* Miscellaneous operators::     
+* Input-output operators::      
+* Conversion operators::        
+@end menu
+
+@node Loading operators, Storing operators, MIX instruction set, MIX instruction set
+@comment  node-name,  next,  previous,  up
+@subsubsection Loading operators
+@cindex loading operators
+
+The following instructions are used to load memory contents into a
+register.
+
+@ftable @code
+@item LDA
+Load rA. OPCODE = 8, MOD = fspec. @code{rA <- V}.
+@item LDX
+Load rX. OPCODE = 15, MOD = fspec. @code{rX <- V}.
+@item LDi
+Load rIi. OPCODE = 8 + i, MOD = fspec. @code{rIi <- V}.
+@item LDAN
+Load rA negative. OPCODE = 16, MOD = fspec. @code{rA <- -V}.
+@item LDXN
+Load rX negative. OPCODE = 23, MOD = fspec. @code{rX <- -V}.
+@item LDiN
+Load rIi negative. OPCODE = 16 + i, MOD = fspec. @code{rIi <- -V}.
+@end ftable
+
+
+@node Storing operators, Arithmetic operators, Loading operators, MIX instruction set
+@comment  node-name,  next,  previous,  up
+@subsubsection Storing operators
+@cindex storing operators
+
+The following instructions are used to store a subfield of a register
+into a memory location.
+
+@ftable @code
+@item STA
+Store rA. OPCODE = 24, MOD = fspec. @code{V <- rA}.
+@item STX
+Store rX. OPCODE = 31, MOD = fspec. @code{V <- rX}.
+@item STi
+Store rIi. OPCODE = 24 + i, MOD = fspec. @code{V <- rIi}.
+@item STJ
+Store rJ. OPCODE = 32, MOD = fspec. @code{V <- rJ}.
+@item STZ
+Store zero. OPCODE = 33, MOD = fspec. @code{V <- 0}.
+@end ftable
+
+
+@node Arithmetic operators, Address transfer operators, Storing operators, MIX instruction set
+@comment  node-name,  next,  previous,  up
+@subsubsection Arithmetic operators
+@cindex arithmetic operators
+
+The following instructions perform arithmetic operations between rA and
+rX register and memory contents.
+
+@ftable @code
+@item ADD
+Add and set OV if overflow. OPCODE = 1, MOD = fspec. 
+@code{rA <- rA +V}.
+@item SUB
+Sub and set OV if overflow. OPCODE = 2, MOD = fspec.
+@code{rA <- rA - V}.
+@item MUL
+Multiply V times rA and store the 10-bytes product in rAX.
+OPCODE = 3, MOD = fspec. @code{rAX <- rA x V}.
+@item DIV
+rAX is considered a 10-bytes number, and it is divided by V.
+OPCODE = 4, MOD = fspec. @code{rA <- rAX / V}, @code{rX} <- reminder.
+@end ftable
+
+@node Address transfer operators, Comparison operators, Arithmetic operators, MIX instruction set
+@comment  node-name,  next,  previous,  up
+@subsubsection Address transfer operators
+@cindex address transfer operators
+
+In these instructions, M (the address of the instruction after indexing)
+is used as a number instead of as the address of a memory cell.
+
+@ftable @code
+@item ENTA
+Enter rA. OPCODE = 48, MOD = 2. @code{rA <- M}.
+@item ENTX
+Enter rX. OPCODE = 55, MOD = 2. @code{rX <- M}.
+@item ENTi
+Enter rIi. OPCODE = 48 + i, MOD = 2. @code{rIi <- M}.
+@item ENNA
+Enter negative rA. OPCODE = 48, MOD = 3. @code{rA <- -M}.
+@item ENNX
+Enter negative rX. OPCODE = 55, MOD = 3. @code{rX <- -M}.
+@item ENNi
+Enter negative rIi. OPCODE = 48 + i, MOD = 3. @code{rIi <- -M}.
+@item INCA
+Increase rA. OPCODE = 48, MOD = 0. @code{rA <- rA + M}.
+@item INCX
+Increase rX. OPCODE = 55, MOD = 0. @code{rX <- rX + M}.
+@item INCi
+Increase rIi. OPCODE = 48 + i, MOD = 0. @code{rIi <- rIi + M}.
+@item DECA
+Decrease rA. OPCODE = 48, MOD = 1. @code{rA <- rA - M}.
+@item DECX
+Decrease rX. OPCODE = 55, MOD = 0. @code{rX <- rX - M}.
+@item DECi
+Decrease rIi. OPCODE = 48 + i, MOD = 0. @code{rIi <- rIi - M}.
+@end ftable
+
+
+@node Comparison operators, Jump operators, Address transfer operators, MIX instruction set
+@comment  node-name,  next,  previous,  up
+@subsubsection Comparison operators
+@cindex comparison operators
+
+The following instructions compare the value of a register with V, and
+set the CM indicator to the result of the comparison.
+
+@ftable @code
+@item CMPA
+Compare rA with V. OPCODE = 56, MOD = fspec.
+@item CMPX
+Compare rX with V. OPCODE = 63, MOD = fspec.
+@item CMPi
+Compare rIi with V. OPCODE = 56 + i, MOD = fspec.
+@end ftable
+
+@node Jump operators, Miscellaneous operators, Comparison operators, MIX instruction set
+@comment  node-name,  next,  previous,  up
+@subsubsection Jump operators
+@cindex jump operators
+
+The following instructions provoke jumps by setting the program
+counter (address of the next instruction to fetch) to M (if a condition
+is met). If a jump occurs, the value of the next instruction address
+that would have been fetched in the absence of the jump is stored in rJ
+(except for @code{JSJ}).
+
+@ftable @code
+@item JMP
+Unconditional jump. OPCODE = 39, MOD = 0.
+@item JSJ
+Unconditional jump, but rJ is not modified. OPCODE = 39, MOD = 1.
+@item JOV
+Jump if OV is set (and turn it off). OPCODE = 39, MOD = 2.
+@item JNOV
+Jump if OV is not set (and turn it off). OPCODE = 39, MOD = 3.
+@item JL
+@itemx JE
+@itemx JG
+@itemx JGE
+@itemx JNE
+@itemx JLE
+Jump according to the value of CM. OPCODE = 39, MOD = 4, 5, 6, 7, 8, 9.
+@item JAN
+@itemx JAZ
+@itemx JAP
+@itemx JANN
+@itemx JANZ
+@itemx JANP
+Jump if the contents of rA is, respectively, negative, zero, positive,
+non-negative, non-zero or non-positive. 
+OPCODE = 40, MOD = 0, 1, 2, 3, 4, 5.
+@item JXN
+@itemx JXZ
+@itemx JXP
+@itemx JXNN
+@itemx JXNZ
+@itemx JXNP
+Jump if the contents of rX is, respectively, negative, zero, positive,
+non-negative, non-zero or non-positive. 
+OPCODE = 47, MOD = 0, 1, 2, 3, 4, 5.
+@item JiN
+@itemx JiZ
+@itemx JiP
+@itemx JiNN
+@itemx JiNZ
+@itemx JiNP
+Jump if the contents of rIi is, respectively, negative, zero, positive,
+non-negative, non-zero or non-positive. 
+OPCODE = 40 + i, MOD = 0, 1, 2, 3, 4, 5.
+@end ftable
+
+@node Miscellaneous operators, Input-output operators, Jump operators, MIX instruction set
+@comment  node-name,  next,  previous,  up
+@subsubsection Miscellaneous operators
+@cindex miscellaneous operators
+
+@ftable @code
+@item SLA
+@itemx SRA
+@itemx SLAX
+@itemx SRAX
+@itemx SLC
+@itemx SRC
+Shift rA or rAX left, right, or rAX circularly left or right. M
+specifies the number of bytes to be shifted.
+OPCODE = 6, MOD = 0, 1, 2, 3, 4, 5.
+@item MOVE
+Move MOD words from M to the location stored in rI1.
+OPCODE = 7, MOD = no. of bytes.
+@item NOP
+No operation. OPCODE = 0, MOD = 0.
+@item HLT
+Halt. Stops instruction fetching. OPCODE = 5, MOD = 2.
+@end ftable
+
+@node Input-output operators, Conversion operators, Miscellaneous operators, MIX instruction set
+@comment  node-name,  next,  previous,  up
+@subsubsection Input-output operators
+@cindex input-output operators
+
+The following instructions perform input-output operations. 
+
+@ftable @code
+@item IN
+Transfer a block of words from the specified unit to memory, starting at
+address M.
+OPCODE = 36, MOD = I/O unit.
+@item OUT
+Transfer a block of words from memory (starting at address M) to the
+specified unit.
+OPCODE = 37, MOD = I/O unit.
+@item IOC
+Perfom a control operation (given by M) on the specified unit.
+OPCODE = 35, MOD = I/O unit.
+@item JRED
+Jump to M if the specified unit is ready.
+OPCODE = 38, MOD = I/O unit.
+@item JBUS
+Jump to M if the specified unit is busy.
+OPCODE = 34, MOD = I/O unit.
+@end ftable
+
+@node Conversion operators,  , Input-output operators, MIX instruction set
+@comment  node-name,  next,  previous,  up
+@subsubsection Conversion operators
+@cindex conversion operators
+
+The following instructions convert between numerical values and their
+character representations.
+
+@ftable @code
+@item NUM
+Convert rAX, assumed to contain a character representation of a number,
+to its numerical value and store it in rA.
+OPCODE = 5, MOD = 0.
+@item CHAR
+Convert the number stored in rA to a character representation and store
+it in rAX.
+OPCODE = 5, MOD = 1.
+@end ftable
+
+@node MIXAL,  , The MIX computer, MIX and MIXAL overview
+@comment  node-name,  next,  previous,  up
+@section MIXAL
+@cindex MIXAL
+@cindex MIX assembly language
+@cindex assembly
+
+The MIX computer can be programmed using an assembly language, MIXAL,
+which provides a symbolic way of writing the binary instructions
+understood by the imaginary MIX computer. If you have used assembler
+languages before, you will find MIXAL a very familiar language. MIXAL is
+fully described in volume 1 of D. Knuth's TAOCP. This section is not
+meant as a replacement of the book's description, but as a brief survey
+of MIXAL.
+
+@menu
+* Instructions::                
+* Comments::                    
+* Expressions::                 
+* Local symbols::               
+* Miscellaneous::               
+@end menu
+
+@node Instructions, Comments, MIXAL, MIXAL
+@comment  node-name,  next,  previous,  up
+@subsection Instructions
+@cindex MIXAL instructions
+@cindex instructions
+@cindex instruction parts
+
+MIX instructions are written in MIXAL according to the following
+pattern:
+
+@example
+[LABEL]   OPCODE  [OPERAND]   [COMMENT]
+@end example
+
+@noindent
+where @samp{OPERAND} is of the form
+
+@example
+[ADDRESS][,INDEX][(MOD)]
+@end example
+
+Items between square brackets are optional, and
+
+@table @code
+@item LABEL
+Is an alphanumeric identifier (a @dfn{symbol}) which gets the value of
+the current compilation address, and can be used in subsequent
+expressions.
+@item OPCODE
+Is a literal denoting the operation code of the instruction
+(e.g. @code{LDA}, @code{STA}) or an assembly pseudoinstruction
+(e.g. @code{ORG}, @code{EQU}).
+@item ADDRESS
+Expression evaluating to the address subfield of the instruction.
+@item INDEX
+Expression evaluating to the index subfield of the instruction. It
+defaults to 0 (i.e., no use of indexing) and can only be used when 
+@code{ADDRESS} is present.
+@item MOD
+Expression evaluating to the mod subfield of the instruction. Its
+default value, when omitted, depends on @code{OPCODE}.
+@item COMMENT
+Any number of spaces after the operand mark the beggining of a comment,
+i.e. any text separated by white space from the operand is ignored by
+the assembler (note that spaces are not allowed within the
+@samp{OPERAND} field).
+@end table
+
+Note that spaces are @emph{not} allowed between the @code{ADDRESS},
+@code{INDEX} and @code{MOD} fields if they are present. White space is
+used to separate the label, operation code and operand parts of the
+instruction@footnote{In fact, Knuth's definition of MIXAL restricts the
+column number at which each of these instruction parts must start. The
+MIXAL assembler included in @sc{mdk}, @code{mixasm}, does not impose
+such restriction.}.
+
+MIXAL instructions can be either one of the MIX machine instructions
+(@pxref{MIX instruction set}) or one of the following assembly
+pseudoinstructions:
+
+@ftable @code
+@item ORIG
+Sets the value of the memory address to which following instructions
+will be allocated after compilation.
+@item EQU
+Used to define a symbol's value, e.g. @w{@code{SYM  EQU  2*200/3}}.
+@item CON
+The value of the given expression is copied directly into the current
+memory address.
+@item ALF
+Takes as operand five characters, constituting the five bytes of a word
+which is copied directly into the current memory address.
+@item END
+Marks the end of the program. Its operand gives the start address for
+program execution.
+@end ftable
+
+Sample MIXAL instructions are
+
+@example
+HERE     LDA  2000
+         LDX  HERE,2(1:3)  this is a comment
+         JMP  1234
+NEXT     STA  HERE*2(8)
+         ORG  4000
+VALUE    EQU  NEXT+HERE//2
+@end example
+
+@node Comments, Expressions, Instructions, MIXAL
+@comment  node-name,  next,  previous,  up
+@subsection Comments
+@cindex comments
+
+Any line starting with an asterisk is treated as a comment and ignored
+by the assembler.
+
+@example
+* This is a comment: this line is ignored.
+    * This line is an error: * must be in column 1.
+@end example
+
+As noted in the previous section, comments can also be located after the
+@samp{OPERAND} field of an instruction, separated from it by white
+space, as in
+
+@example
+LABEL     LDA   100  This is also a comment
+@end example
+
+@node Expressions, Local symbols, Comments, MIXAL
+@comment  node-name,  next,  previous,  up
+@subsection Expressions
+@cindex operator
+@cindex binary operator
+@cindex unary operator
+The @code{ADDRESS}, @code{INDEX} and @code{MOD} fields of a MIXAL
+instruction can be expressions, formed by numbers, identifiers and
+binary operators (@code{+ - * / // :}). @code{+} and @code{-} can also
+be used as unary operators. Order of evaluation is from left to right:
+there is no other operator precedence rule, and parentheses cannot be
+used for grouping. A stand-alone asterisk denotes the current memory
+location; thus, for instance,
+
+@example
+     4+2**
+@end example
+
+@noindent
+evaluates to 4 plus two times the current memory location. White space
+is not allowed within expressions.
+
+All symbols appearing within an expression must be defined. Future
+references are only allowed when appearing stand-alone (or modified by
+an unary operator) in the @code{ADDRESS} part of a MIXAL instruction,
+e.g.
+
+@example
+* OK: stand alone future reference 
+         STA  -S1(1:5)
+* ERROR: future reference in expression
+         LDX  2-S1
+S1       LD1  2000
+@end example
+
+@node Local symbols, Miscellaneous, Expressions, MIXAL
+@comment  node-name,  next,  previous,  up
+@subsection Local symbols
+@cindex local symbols
+
+Besides user defined symbols, MIXAL programmers can use the so called
+@dfn{local symbols}, which are symbols of the form @code{[1-9][HBF]}. A
+local symbol @code{nB} refers to the address of the last previous
+occurrence of @code{nH} as a label, while @code{nF} refers to the next
+@code{nH} occurrence. Unlike user defined symbols, @code{nH} can appear
+multiple times in the @code{LABEL} part of different MIXAL
+instructions. The following code shows an instance of local symbols'
+usage:
+
+@example
+* line 1
+1H    LDA  100
+* line 2: 1B refers to address of line 1, 3F refers to address of line 4
+      STA  3F,2(1B//2)
+* line 3: redefinition of 1H
+1H    STZ
+* line 4: 1B refers to address of line 3
+3H    JMP  1B
+@end example
+
+@node Miscellaneous,  , Local symbols, MIXAL
+@comment  node-name,  next,  previous,  up
+@subsection Miscellaneous
+@cindex literal constants
+
+MIXAL allows the introduction of @dfn{literal constants}, which are
+automatically stored in memory addresses after the end of the program by
+the assembler. Literal constants are denoted as @code{=exp=}, where
+@code{exp} is an expression. For instance, the code
+
+@example
+L         EQU   10
+          LDA   =20-L=
+@end example
+
+causes the assembler to add after the program's end an instruction with
+contents 10, and to assemble the above code as the instruction @w{@code{
+LDA a}}, where @code{a} stands for the address in which the value 10 is
+stored. In other words, the compiled code is equivalent to the
+following:
+
+@example
+L         EQU  10
+          LDA  a
+@dots{}
+a         CON  20-L    
+          END  start
+@end example
+
+
+@node Getting started, mixvm, MIX and MIXAL overview, Top
+@comment  node-name,  next,  previous,  up
+@chapter Getting started
+
+In this chapter, you will find a sample code-compile-run-debug session
+using the @sc{mdk} utilities. Familiarity with the MIX mythical computer
+and its assembly language MIXAL (as described in Knuth's TAOCP) is
+assumed; for a compact reminder, see @ref{MIX and MIXAL overview}. 
+
+@menu
+* Writing a source file::       A sample MIXAL source file.
+* Compiling::                   Using @code{mixasm} to compile source
+                                files into binary format.
+* Running the program::         Running and debugging your program.
+@end menu
+
+@node Writing a source file, Compiling, Getting started, Getting started
+@comment  node-name,  next,  previous,  up
+@section Writing a source file
+@cindex MIXAL
+@cindex source file
+
+MIXAL programs can be written as ASCII files with your editor of choice.
+Here you have the mandatory @emph{hello world} as written in the MIXAL
+assembly language:
+
+@example
+*                                                        (1)
+* hello.mixal: say 'hello world' in MIXAL                (2)
+*                                                        (3)
+* label ins    operand     comment                       (4)
+TERM    EQU    19          the MIX console device number (5)
+        ORIG   1000        start address                 (6)
+START   OUT    MSG(TERM)   output data at address MSG    (7)
+        HLT                halt execution                (8)
+MSG     ALF    "MIXAL"                                   (9)
+        ALF    " HELL"                                   (10)
+        ALF    "O WOR"                                   (11)
+        ALF    "LD   "                                   (12)
+        END    START       end of the program            (13)
+@end example
+         
+@noindent MIXAL source files should have the extension @file{.mixal}
+when used with the @sc{mdk} utilities. As you can see in the above
+sample, each line in a MIXAL file can be divided into four fields
+separated by an arbitrary amount of whitespace characters (blanks and or
+tabs). While Knuth's definition of MIXAL each field must start at a
+fixed pre-defined column number, the @sc{mdk} assembler loosens this
+requirement and lets you format the file as you see fit. The only
+restrictions retained are for comment lines (like 1-4) which must begin
+with an asterisk (*) placed at column 1, and for the label field (see
+below) which, if present, must also start at column 1. The four fields
+in each non-comment line are:
+
+@itemize @minus
+@item
+an optional label, which either refers to the current memory address (as
+@code{START} and @code{MSG} in lines 7 and 9) or a defined symbol
+(@code{TERM}) (if present, the label must always start at the first
+column in its line, for the first whitespace in the line maks the
+beginning of the second field),
+@item
+an operation mnemonic, which can represent either a MIX instruction
+(@code{OUT} and @code{HLT} in lines 6 and 7 above), or an assembly
+pseudoinstruction.
+@item
+an optional operand for the (pseudo)instruction, and
+@item
+an optional free text comment.
+@end itemize
+
+@noindent Lines 9-12 of the @file{hello.mixal} file above also show the
+second (and last) difference between Knuth's MIXAL definition and ours:
+the operand of the @code{ALF} pseudoinstruction (a word of five
+characters) must be quoted with using ""@footnote{In Knuth's definition,
+the operand always starts at a fixed column number, and the use of
+quotation is therefore unnecessary. As @code{mixasm} releases this
+requirement, marking the beginning and end of the @code{ALF} operand
+disambiguates the parser's recognition of this operand when it includes
+blanks}. 
+
+The workings of this sample program should be straightforward if you are
+familiar with MIXAL. See TAOCP vol. 1 for a thorought definition or
+@ref{MIX and MIXAL overview}, for a quick tutorial.
+
+@node Compiling, Running the program, Writing a source file, Getting started
+@comment  node-name,  next,  previous,  up
+@section Compiling
+@cindex compiling
+@cindex binary programs
+@cindex virtual machine
+@cindex assembler
+@cindex @code{mixasm}
+
+A simulator of the MIX computer, called @code{mixvm} (MIX virtual
+machine) is included in the @sc{mdk} tools. It is able to run binary
+files containing MIX instructions written in their binary
+representation. You can translate MIXAL source files into this binary
+form using @code{mixasm}, the MIXAL assembler. So, in order to compile
+the @file{hello.mixal} file, you can type the following 
+command at your shell prompt:
+
+@example
+mixasm -g hello @key{RET}
+@end example
+
+If the source file contains no errors, this will produce a binary file
+called @file{hello.mix} which can be loaded and run by the MIX virtual
+machine. The @code{-g} flag tells the assembler to include debug
+information in the executable file (for a complete description of all
+the compilation options, see @ref{mixasm}.) Now, your are ready to run
+your first MIX program, as described in the following section.
+
+
+@node Running the program,  , Compiling, Getting started
+@comment  node-name,  next,  previous,  up
+@section Running the program
+@cindex @code{mixvm}
+@cindex non-interactive mode
+@cindex interactive mode
+
+MIX is a mythical computer, so it is no use ordering it from your
+favorite hardware provider. @sc{mdk} provides a software simulator of
+the computer, though. It is called @code{mixvm}, which stands for
+@dfn{MIX virtual machine}. Using it, you can run your MIXAL programs,
+after compiling them with @code{mixasm} into binary @file{.mix}
+files. @code{mixvm} can be used either in @dfn{interactive} or
+@dfn{non-interactive} mode. In the second case, @code{mixvm} will load
+your program into memory, execute it (producing any output due to MIXAL
+@code{OUT} instructions present in the program), and exit when it
+encounters a @code{HLT} instruction. In interactive mode, you will enter
+a shell prompt which allows you issuing commands to the running virtual
+machine. This commands will permit you loading, running and debugging
+programs, as well as inspecting the MIX computer state (register
+contents, memory cells contents and so on).
+
+@menu
+* Non-interactive mode::        Running your programs non-interactively.
+* Interactive mode::            Running programs interactively.
+* Debugging::                   Commands for debugging your programs.
+@end menu
+
+@node Non-interactive mode, Interactive mode, Running the program, Running the program
+@comment  node-name,  next,  previous,  up
+@subsection Non-interactive mode
+@cindex non-interactive mode
+
+To make @code{mixvm} work in non-interactive mode, use the @code{-r}
+flag. Thus, to run our @file{hello.mix} program, simply type
+
+@example
+mixvm -r hello @key{RET}
+@end example
+
+@noindent at your command prompt, and you will get the following output:
+
+@example
+MIXAL HELLO WORLD
+@end example
+
+@noindent Since our hello world program uses MIX's device number 19 as
+its output device (@pxref{Writing a source file}), the output is
+redirected to the shell's standard output. Had you used any other MIX
+output devices (disks, drums, line printer, etc.), @code{mixvm} would
+have created a file named after the device used (e.g. @file{disk4.dev})
+and written its output there.
+
+Sometimes, you will prefer to store the results of your program in MIX
+registers rather than writing them to a device. In such cases,
+@code{mixvm}'s @code{-d} flag is your friend: it makes @code{mixvm} to
+dump the contents of its registers and flags after executing the loaded
+program. For instance, typing the following command at your shell's
+prompt
+
+@example
+mixvm -d -r hello
+@end example
+
+@noindent you will obtain the following output:
+
+@example
+MIXAL HELLO WORLD
+rA: + 00 00 00 00 00 (0000000000)
+rX: + 00 00 00 00 00 (0000000000)
+rJ: + 00 00 (0000)
+rI1: + 00 00 (0000)     rI2: + 00 00 (0000)     
+rI3: + 00 00 (0000)     rI4: + 00 00 (0000)     
+rI5: + 00 00 (0000)     rI6: + 00 00 (0000)     
+Overflow: F
+Cmp: E
+@end example
+
+@noindent which, in addition to the program's outputs, gives you the
+contents of the MIX registers and the values of the overflow toggle and
+comparison flag (admittedly, rather uninteresting in our sample).
+
+As you can see, running programs non-interactively has many
+limitations. You cannot peek the virtual machine's memory contents, not
+to mention stepping through your program's instructions or setting
+breakpoints. Enter interactive mode.
+
+@node Interactive mode, Debugging, Non-interactive mode, Running the program
+@comment  node-name,  next,  previous,  up
+@subsection Interactive mode
+@cindex interactive mode
+
+To enter the MIX virtual machine interactive mode, simply type
+
+@example
+mixvm @key{RET}
+@end example
+
+@noindent at your shell command prompt. This command enters the
+@code{mixvm} command shell. You will be presented the following command
+prompt:
+
+@example
+MIX >
+@end example
+
+@noindent The virtual machine is initialised and ready to accept your
+commands. The @code{mixvm} command shell uses GNU's readline, so that
+you have at your disposal command completion (using @key{TAB}) and
+history functionality, as well as other line editing shortcuts common to
+all utilities using this library (for a complete description of
+readline's line editing usage, see @ref{Command Line
+Editing,,,Readline}.)
+
+Usually, the first thing you will want to do is loading a compiled MIX
+program into memory. This is acomplished by the @code{load} command,
+which takes as an argument the name of the @file{.mix} file to be
+loaded. Thus, typing
+
+@example
+MIX > load hello @key{RET}
+Program loaded. Start address: 3000
+MIX >
+@end example
+
+@noindent will load @file{hello.mix} into the virtual machine's memory
+and set the program counter to the address of the first instruction. You
+can obtain the contents of the program counter using the command
+@code{pc}:
+
+@example
+MIX > pc
+Current address: 3000
+MIX >
+@end example
+
+After loading it, you are ready to run the program,
+using, as you surely have guessed, the @code{run} command:
+
+@example
+MIX > run
+Running ...
+MIXAL HELLO WORLD                                                     
+... done
+MIX > 
+@end example
+
+@noindent After running the program, the program counter will point to
+the address after the one containing the @code{HLT} instruction. In our
+case, asking the value of the program counter after executing the
+program will give us
+
+@example
+MIX > pc
+Current address: 3002
+MIX >
+@end example
+
+@noindent You can check the contents of a memory cell giving its address
+as an argument of the command @code{pmem}, like this
+
+@example
+MIX > pmem 3001
+3001: + 00 00 00 02 05 (0000000133)
+MIX >
+@end example
+
+@noindent
+and convince yourself that address 3001 contains the binary
+representation of the instruction @code{HLT}. An address range of the
+form FROM-TO can also be used as the argument of @code{pmem}:
+
+@example
+MIX > pmem 3000-3006
+3000: + 46 58 00 19 37 (0786957541)
+3001: + 00 00 00 02 05 (0000000133)
+3002: + 14 09 27 01 13 (0237350989)
+3003: + 00 08 05 13 13 (0002118477)
+3004: + 16 00 26 16 19 (0268542995)
+3005: + 13 04 00 00 00 (0219152384)
+3006: + 00 00 00 00 00 (0000000000)
+MIX >
+@end example
+
+@noindent
+In a similar manner, you can look at the contents of the MIX registers
+and flags. For instance, to ask for the contents of the A register you
+can type
+
+@example
+MIX > preg A
+rA: + 00 00 00 00 00 (0000000000)
+MIX >
+@end example
+
+@noindent
+Use the comand @code{help} to obtain a list of all available commands,
+and @code{help COMMAND} for help on a specific command, e.g.
+
+@example
+MIX > help run
+run             Run loaded or given MIX code file. Usage: run [FILENAME]
+MIX > 
+@end example
+
+@noindent
+For a complete list of commands available at the MIX propmt,
+@xref{mixvm}. In the following subsection, you will find a quick tour
+over commands useful for debugging your programs.
+
+@node Debugging,  , Interactive mode, Running the program
+@comment  node-name,  next,  previous,  up
+@subsection Debugging commands
+
+The interactive mode of @code{mixvm} lets you step by step execution of
+programs as well as breakpoint setting. Use @code{next} to step through
+the program, running its instructions one by one. To run our
+two-instruction @file{hello.mix} sample you can do the following:
+
+@example
+MIX > load hello
+Program loaded. Start address: 3000
+MIX > pc
+Current address: 3000
+MIX > next
+MIXAL HELLO WORLD                                                     
+MIX > pc
+Current address: 3001
+MIX > next
+MIX > pc
+Current address: 3002
+MIX > next
+End of program reached at address 3002
+MIX > 
+@end example
+
+You can set a breakpoint at a given address using the command
+@code{sbpa} (set breakpoint at address). When a breakpoint is set,
+@code{run} will stop before executing the instruction at the given
+address. Typing @code{run} again will resume program execution. Coming
+back to our hello world example, we would have:
+
+@example
+MIX > sbpa 3001
+Breakpoint set at address 3001
+MIX > run
+Running ...
+MIXAL HELLO WORLD                                                     
+... stopped: breakpoint at line 8 (address 3001)
+MIX > run
+Running ...
+... done
+MIX >
+@end example
+
+@noindent
+Note that, since we compiled @file{hello.mixal} with debug info enabled
+(the @code{-g} flag of @code{mixasm}), the virtual machine is able to
+tell us the line in the source file corresponding to the breakpoint we
+are setting. As a matter of fact, you can directly set breakpoints at
+source code lines using the command @code{sbp LINE_NO}, e.g.
+
+@example
+MIX > sbp 4
+Breakpoint set at line 7
+MIX > 
+@end example
+
+@noindent
+@code{sbp} sets the breakpoint at the first meaningful source code line;
+thus, in the above example we have requested a breakpoint at a line
+which does not correspond to a MIX instruction and the breakpoint is set
+at the first line containing a real instruction after the given one. To
+unset breakpoints, use @code{cbpa ADDRESS} and @code{cbp LINE_NO}, or
+@code{cabp} to remove all currently set breakpoints. 
+
+MIXAL lets you define symbolic constants, either using the @code{EQU}
+pseudoinstruction or starting an instruction line with a label (which
+assigns to the label the value of the current memory address). Each
+MIXAL program has, therefore, an associated symbol table which you can
+inspect using the @code{psym} command. For our hello world sample, you
+will obtain the following output:
+
+@example
+MIX > psym
+START:  3000
+TERM:  19
+MSG:  3002
+MIX > 
+@end example
+
+For a complete description of all available MIX commands, @xref{mixvm}.
+
+
+
+@node mixvm, mixasm, Getting started, Top
+@comment  node-name,  next,  previous,  up
+@chapter @code{mixvm}, the MIX computer simulator
+
+@cindex mixvm
+
+This chapter describes @code{mixvm}, the MIX computer
+simulator. @code{mixvm} is a command line interface programme which
+simulates the MIX computer (@pxref{The MIX computer}). It is able
+to run MIXAL programs (@pxref{MIXAL}) previously compiled with the MIX
+assembler (@pxref{mixasm}). The simulator allows inspection of the MIX
+computer components (registers, memory cells, comparison flag and overflow
+toggle), step by step execution of MIX programmes, and breakpoint
+setting to aid you in debugging your code. For a tutorial description of
+@code{mixvm} usage, @xref{Running the program}.
+
+@menu
+* Invocation::                  Options when invoking @code{mixvm}.
+* Commands::                    Commands available in interactive mode.
+* Devices::                     MIX block devices implementation.
+@end menu
+
+@node Invocation, Commands, mixvm, mixvm
+@comment  node-name,  next,  previous,  up
+@section Invoking @code{mixvm}
+
+@code{mixvm} can be invoked with the following command line options
+(note, that, following GNU's conventions, we provide a long option name
+for each available single letter switch):
+
+@example
+mixvm [-vhurd] [--version] [--help] [--usage] [--run] [--dump]
+      [FILE[.mix]]
+@end example
+
+@noindent
+The meaning of these options is as follows:
+
+@defopt -v
+@defoptx --version
+Prints version and copyleft information and exits.
+@end defopt
+
+@defopt -h
+@defoptx --help
+@defoptx -u
+@defoptx --usage
+Prints a summary of available options and exits.
+@end defopt
+
+@defopt -r
+@defoptx --run
+Loads the specified @var{FILE} and executes it. After the program
+execution, @code{mixvm} exits. @var{FILE} must be the name of a binary
+@file{.mix} program compiled with @code{mixasm}. If your program does
+not produce any output, use the @code{-d} flag (see below) to peek at
+the virtual machine's state after execution.
+@end defopt
+
+@defopt -d
+@defoptx --dump
+This option must be used in conjuction with @code{-r}, and tells
+@code{mixvm} to print the value of the virtual machine's registers,
+comparison flag and overflow toggle after executing the program named
+@var{FILE}. See @xref{Non-interactive mode}, for sample usage.
+@end defopt
+
+When run without the @code{-r} flag, @code{mixvm} enters its interactive
+mode, showing you a prompt like this one:
+
+@example
+MIX >
+@end example
+
+@noindent
+and waiting for your commands (@pxref{Commands}). If the
+optional @var{FILE} argument is given, the file @file{FILE.mix} will be
+loaded into the virtual machine memory before entering the interactive
+mode. 
+
+@node Commands, Devices, Invocation, mixvm
+@comment  node-name,  next,  previous,  up
+@section Interactive commands 
+
+You can enter the interactive mode of the MIX virtual machine by simply
+invoking @code{mixvm} without arguments. You will then presented a shell
+prompt 
+
+@example
+MIX >
+@end example
+
+@noindent
+which indicates that a new virtual machine has been initialised and is
+ready to execute your commands. As we have already mentioned, this
+command prompt offers you command line editing facilities as described
+in the Readline user's manual (chances are that you are already familiar
+with these command line editing capabilities, as they are present in
+many GNU utilities, e.g. the @code{bash} shell). As a beginner, your
+best friend will be the @code{help} command, which shows you a summary
+of all available MIX commands and their usage; its syntax is as follows:
+
+@deffn {@code{mixvm} command} help [command]
+@deffnx {@code{mixvm} command} ? [command]
+Prints a short description of the given @var{command} and its usage. If
+@var{command} is omitted, all available commands are described.
+@end deffn
+
+You have at your disposal a series of commands that let you load and
+execute MIX executable file, as well as manipulate MIXAL source files:
+
+@deffn {file command} load file[.mix]
+This command loads a binary file, @var{file.mix} into the virtual
+machine memory, and positions the program counter at the beginning of
+the loaded program. This address is indicated in the MIXAL source file
+as the operand of the @code{END} pseudoinstruction. Thus, if your
+@file{sample.mixal} source file contains the line:
+
+@example
+     END 3000
+@end example
+
+@noindent
+and you compile it with @code{mixasm} to produce the binary file
+@file{sample.mix}, you will load it into the virtual machine as follows:
+
+@example
+MIX > load sample
+Program loaded. Start address: 3000
+MIX >
+@end example
+
+@end deffn
+
+@deffn {file command} run [file[.mix]]
+When executed without argument, this command initiates or resumes
+execution of instructions from the current program counter
+address. Therefore, issuing this command after a successful @code{load},
+will run the loaded program until either a @code{HLT} instruction or a
+breakpoint is found. If you provide a MIX filename as argument, the
+given file will be loaded (as with @code{load} @var{file}) and
+executed. If @code{run} is invoked again after program execution
+completion (i.e., after the @code{HLT} instruction has been found in a
+previous run), the program counter is repositioned and execution starts
+again from the beginning. 
+@end deffn
+
+@deffn {file command} edit file[.mixal]
+The source file @var{file.mixal} is edited using the editor defined in
+the environment variable @var{MIX_EDITOR}. If this variable is not set,
+the following ones are tried out in order: @var{X_EDITOR}, @var{EDITOR}
+and @var{VISUAL}.
+@end deffn
+
+@deffn {file command} compile file[.mixal]
+The source file @var{file.mixal} is compiled (with debug information
+enabled) using @code{mixasm}.
+@end deffn
+
+Sequential execution of loaded programs can be interrupted using the
+following debug commands:
+
+@deffn {debug command} next [ins_number]
+This command causes the virtual machine to fetch and execute  up to
+@var{ins_number} instructions, beginning from the current program
+counter position. Execution is interrupted either when the specified
+number of instructions have been fetched or a breakpoint is found,
+whatever happens first. If run without arguments, one instruction is
+executed. 
+@end deffn
+
+@deffn {debug command} sbp line_number
+Sets a breakpoint at the specified source file line number. If the line
+specified corresponds to a command or to a MIXAL pseudoinstruction which
+does not produce a MIX instruction in the binary file (such as
+@code{ORIG} or @code{EQU}) the breakpoint is set at the first source
+code line giving rise to a MIX instruction after the specified
+one. Thus, for our sample @file{hello.mixal} file:
+
+@example
+*                                                        (1)
+* hello.mixal: say 'hello world' in MIXAL                (2)
+*                                                        (3)
+* label ins    operand     comment                       (4)
+TERM    EQU    19          the MIX console device number (5)
+        ORIG   1000        start address                 (6)
+START   OUT    MSG(TERM)   output data at address MSG    (7)
+...
+@end example
+
+@noindent
+trying to set a breakpoint at line 5, will produce the following result:
+
+@example
+MIX > sbp 5
+Breakpoint set at line 7
+MIX > 
+@end example
+
+@noindent
+since line 7 is the first one compiled into a MIX instruction (at
+address 3000). In order to @code{sbp} to work, the source file must be
+compiled using the @code{-g} flags, which tells @code{mixasm} to include
+debug information in the binary @file{.mix} file.
+@end deffn
+
+@deffn {debug command} spba address
+Sets a breakpoint at the given memory @var{address}. The argument must
+be a valid MIX memory address, i.e., it must belong into the range
+@w{[0-3999]}. Note that no check is performed to verify that the
+specified address is reachable during program execution. No debug
+information is needed to set a breakpoint by address with @code{sbpa}.
+@end deffn
+
+@deffn {debug command} cbp line_no
+Clears a (previously set) breakpoint at the given source file line.
+@end deffn
+
+@deffn {debug command} cbpa address
+Clears a (previously set) breakpoint at the given memory address.
+@end deffn
+
+@deffn {debug command} cabp
+Clears all currently set breakpoints.
+@end deffn
+
+@deffn {debug command} psym [symbol_name]
+MIXAL programs can define symbolic constants, using either the
+@code{EQU} pseudoinstruction or a label at the beginning of a
+line. Thus, in the program fragment
+
+@example
+VAR     EQU  2168
+        ORIG 4000
+START   LDA  VAR
+@end example
+
+@noindent
+the symbol @code{VAR} stands for the value 2168, while @code{START} is
+assigned the value 4000. When MIXAL programs are compiled using the
+@code{-g} flag (which tells @code{mixasm} to include debug information
+in the binary @file{.mix} file), the symbol table can be consulted from
+the @code{mixvm} command line using @code{psym} followed by the name of
+the symbol whose contents you are interested in. When run without
+arguments, @code{psym} will print all defined symbols and their values.
+@end deffn
+
+Inspection and modification of the virtual machine state (memory,
+registers, overflow toggle and comparison flag contents) is accomplished
+using the following commands:
+
+@deffn {state command} pc
+Prints the current value of the program counter, which stores the
+address of the next instruction to be executed in a non-halted program.
+@end deffn
+
+@deffn {state command} preg [A | X | J | I[1-6]]
+@deffnx {state command} pall
+@deffnx {state command} sreg A | X | J | I[1-6] value
+@code{preg} prints the contents of a given MIX register. For instance,
+@w{@code{preg} @var{A}} will print the contents of the A-register. When
+invoked without arguments, all registers shall be printed:
+
+@example
+MIX > preg
+rA: - 00 00 00 00 35 (0000000035)
+rX: + 00 00 00 15 40 (0000001000)
+rJ: + 00 00 (0000)
+rI1: + 00 00 (0000)	rI2: + 00 00 (0000)	
+rI3: + 00 00 (0000)	rI4: + 00 00 (0000)	
+rI5: + 00 00 (0000)	rI6: + 00 00 (0000)	
+MIX > 
+@end example
+
+As you can see in the above sample, the contents is printed as the sign
+plus the values of the MIX bytes stored in the register and, between
+parenthesis, the decimal representation of its module.
+
+@code{pall} prints the contents of all registers plus the comparison
+flag and overflow toggle.
+
+Finally, @code{sreg} Sets the contents of the given register to
+@var{value}, expressed as a decimal constant. If @var{value} exceeds the
+maximum value storable in the given register, @math{VALUE mod
+MAXIMU_VALUE} is stored, e.g.
+
+@example
+MIX > sreg I1 1000
+MIX > preg I1
+rI1: + 15 40 (1000)	
+MIX > sreg I1 1000000
+MIX > preg I1
+rI1: + 09 00 (0576)	
+MIX > 
+@end example
+
+@end deffn
+
+
+@deffn {state command} pflags
+@deffnx {state command} scmp E | G | L
+@deffnx {state command} sover F | T
+@code{pflags} prints the value of the comparison flag and overflow
+toggle of the virtual machine, e.g.
+
+@example
+MIX > pflags
+Overflow: F
+Cmp: E
+MIX > 
+@end example
+
+@noindent
+The values of the overflow toggle are either @var{F} (false) or @var{T}
+(true), and, for the comparison flag, @var{E}, @var{G}, @var{L} (equal,
+greater, lesser). @code{scmp} and @code{sover} are setters of the
+comparison flag and overflow toggle values.
+@end deffn
+
+@deffn {state command} pmem from[-to]
+@deffnx {state command} smem address value
+@code{pmem} prints the contents of memory cells in the address range
+@w{[@var{FROM}-@var{TO}]}. If the upper limit @var{to} is omitted, only
+the contents of the memory cell with address @var{FROM} is printed, as
+in
+
+@example
+MIX > pmem 3000
+3000: + 46 58 00 19 37 (0786957541)
+MIX >
+@end example
+
+The memory contents is displayed both as the set of five MIX bytes plus
+sign composing the stored MIX word and, between parenthesis, the decimal
+representation of the module of the stored value.
+
+@code{smem} sets the content of the memory cell with address
+@var{address} to @var{value}, expressed as a decimal constant.
+
+@end deffn
+
+Finally, you can use the @code{quit} command to exit @code{mixvm}.
+
+@node Devices,  , Commands, mixvm
+@comment  node-name,  next,  previous,  up
+@section MIX block devices
+
+The MIX computer comes equipped with a set of block devices for
+input-output operations (@pxref{Input-output operators}). @code{mixvm}
+implements these block devices as disk files, with the exception of
+block device no. 19 (typewriter terminal) which is redirected to
+standard output. When you request an output operation on any other
+(output) device, a file named according to the following table will be
+created in the current directory, and the specified MIX words will be
+written to the file in binary form (for binary devices) or in ASCII (for
+char devices). Files corresponding to input block devices should be
+created and filled beforehand to be used by the MIX virtual machine (for
+input-output devices this creation can be accomplished by a MIXAL
+program writing to the device the required data, or, if you prefer, with
+your favourite editor).
+
+@multitable {the device name} {xx-xx} {filena[x-x].dev} {bin  i/o} 
+@item @emph{Device}  @tab @emph{No.} @tab @emph{filename} @tab @emph{type}
+@item Tape @tab 0-7 @tab @file{tape[0-7].dev} @tab bin i/o
+@item Disks @tab 8-15 @tab @file{disk[0-7].dev} @tab bin i/o
+@item Card reader @tab 16 @tab @file{cardrd.dev} @tab char in
+@item Card writer @tab 17 @tab @file{cardwr.dev} @tab char out
+@item Line printer @tab 18 @tab @file{printer.dev} @tab char out
+@item Terminal @tab 19 @tab @code{stdout} @tab char out
+@item Paper tape @tab 20 @tab @file{paper.dev} @tab char out
+@end multitable
+
+
+
+@node mixasm, Copying, mixvm, Top
+@comment  node-name,  next,  previous,  up
+@chapter @code{mixasm}, the MIXAL assembler
+@cindex @code{mixasm}
+@cindex MIXAL
+@cindex assembler
+
+MIX programs, as executed by @code{mixvm}, are composed of binary
+instructions loaded into the virtual machine memory as MIX
+words. Although you could write your MIX programs directly as a series
+of words in binary format, you have at your disposal a more friendly
+assembly language, MIXAL (@pxref{MIXAL}) which is compiled into binary
+form by @code{mixasm}, the MIXAL assembler included in @sc{mdk}. In this
+chapter, you will find a complete description of @code{mixasm} options.
+
+@menu
+* Invoking @code{mixasm}::      @code{mixasm} options
+@end menu
+
+@node Invoking @code{mixasm},  , mixasm, mixasm
+@comment  node-name,  next,  previous,  up
+@section Invoking @code{mixasm}
+
+In its simplest form, @code{mixasm} is invoked with a single argument,
+which is the name of the MIXAL file to be compiled, e.g.
+
+@example
+mixasm hello
+@end example
+
+@noindent
+will compile either @file{hello} or @file{hello.mixal}, producing a
+binary file named @file{hello.mix} if no errors are found.
+
+In addition, @code{mixasm} can be invoked with the following command
+line options (note, that, following GNU's conventions, we provide a long
+option name for each available single letter switch):
+
+@example
+mixasm [-vhulg] [-o OUTPUT_FILE] [--version] [--help]
+       [--usage] [--debug] [--output=OUTPUT_FILE] [--list[=LIST_FILE]] file
+@end example
+
+@noindent
+The meaning of these options is as follows:
+
+@defopt -v
+@defoptx --version
+Prints version and copyleft information and exits.
+@end defopt
+
+@defopt -h
+@defoptx --help
+@defoptx -u
+@defoptx --usage
+Prints a summary of available options and exits.
+@end defopt
+
+@defopt -g
+@defoptx --debug
+Includes debugging information in the compiled file, allowing breakpoint
+setting at source level and symbol table inspection under @code{mixvm}.
+@end defopt
+
+@defopt -o output_file
+@defoptx --output=output_file
+By default, the given source file @var{file.mixal} is compiled into
+@var{file.mix}. You can provide a different name for the output file
+using this option.
+@end defopt
+
+@defopt -l
+@defoptx --list[=list_file]
+This option causes @code{mixasm} to produce, in addion to the
+@file{.mix} file, an ASCII file containing a summary of the compilation
+results. The file is named after the MIXAL source file, changing its
+extension to @file{.mls} if no argument is provided; otherwise, the
+listing file is named according to the argument.
+@end defopt
+
+
+
+@node Copying, Problems, mixasm, Top
+@chapter Copying
+@lowersections
+@include gpl.texi
+@raisesections
+
+@node Problems, Concept Index, Copying, Top
+@chapter Reporting Bugs
+@cindex bugs
+@cindex problems
+
+If you find a bug in @sc{mdk} (or have questions, comments or suggestions
+about it), please send electronic mail to @email{jaortega@@acm.org,
+the author}. 
+
+In your report, please include the version number, which you can find by
+running @w{@samp{mixasm --version}}.  Also include in your message the
+output that the program produced and the output you expected.
+
+@node Concept Index,  , Problems, Top
+@unnumbered Concept Index
+
+@cindex tail recursion
+@printindex cp
+
+@c @node MIXAL instructions,  , Concept Index, Top
+@comment  node-name,  next,  previous,  up
+@c @unnumbered MIXAL instructions
+@c @printindex fn
+
+@shortcontents
+@contents
+@bye
diff --git a/mixlib/.cvsignore b/mixlib/.cvsignore
new file mode 100644
index 0000000..d2486ce
--- /dev/null
+++ b/mixlib/.cvsignore
@@ -0,0 +1,5 @@
+.deps
+Makefile
+Makefile.in
+mix_scanner.c
+
diff --git a/mixlib/Makefile.am b/mixlib/Makefile.am
new file mode 100644
index 0000000..26355cf
--- /dev/null
+++ b/mixlib/Makefile.am
@@ -0,0 +1,37 @@
+## Process this file with automake to produce Makefile.in
+
+# Copyright (C) 2000 jose antonio ortega ruiz <jaortega@retemail.es>
+#  
+# This file is free software; as a special exception the author gives
+# unlimited permission to copy and/or distribute it, with or without 
+# modifications, as long as this notice is preserved.
+# 
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+SUBDIRS = testsuite
+INCLUDES = -I$(includedir) -DG_LOG_DOMAIN=\"libmix\"
+
+noinst_LIBRARIES = libmix.a
+libmix_a_SOURCES = mix.h mix.c \
+		   mix_types.h mix_types.c \
+		   mix_ins.h mix_ins.c     \
+	           mix_vm.h mix_vm.c xmix_vm.h xmix_vm.c \
+		   mix_vm_dump.h mix_vm_dump.c \
+		   mix_io.h mix_io.c xmix_io.h xmix_io.c \
+		   mix_symbol_table.h mix_symbol_table.c \
+		   mix_file.h mix_file.c \
+                   mix_code_file.h mix_code_file.c \
+		   mix_parser.h xmix_parser.h mix_parser.c mix_scanner.l \
+                   mix_device.h mix_device.c
+
+
+
+
+
+
+
+
+
+
diff --git a/mixlib/mix.c b/mixlib/mix.c
new file mode 100644
index 0000000..14e4c13
--- /dev/null
+++ b/mixlib/mix.c
@@ -0,0 +1,63 @@
+/* -*-c-*- -------------- mix.c :
+ * Implementation of the functions declared in mix.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#include "mix_types.h"
+#include "mix_ins.h"
+#include "mix_code_file.h"
+#include "mix.h"
+
+
+/* This function must be called before using the library */
+void 
+mix_init_lib(void)
+{
+  mix_init_types ();
+  mix_init_ins ();
+  mix_code_file_set_defext (MIX_CODE_DEFEXT);
+}
+
+
+/* This function must be called for deallocating the lib resources
+   when it is no longer in use 
+*/
+void
+mix_release_lib (void)
+{
+  /* clean the user defined code file extension (if any) */
+  mix_code_file_set_defext (NULL); 
+  mix_release_ins ();
+}
+
+const char *MIX_GPL_LICENSE = 
+"Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>\n" 
+"This program is free software; you can redistribute it and/or modify\n"
+"it under the terms of the GNU General Public License as published by\n"
+"the Free Software Foundation; either version 2 of the License, or\n"
+"(at your option) any later version.\n"
+"This program is distributed in the hope that it will be useful,\n"
+"but WITHOUT ANY WARRANTY; without even the implied warranty of\n"
+"MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n"
+"GNU General Public License for more details.\n"
+"You should have received a copy of the GNU General Public License\n"
+"along with this program; if not, write to the Free Software\n"
+"Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.\n";
+
diff --git a/mixlib/mix.h b/mixlib/mix.h
new file mode 100644
index 0000000..a75bbcd
--- /dev/null
+++ b/mixlib/mix.h
@@ -0,0 +1,65 @@
+/* -*-c-*- ---------------- mix.h :
+ * Initialisation of the mix library
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIX_H
+#define MIX_H
+
+#ifdef HAVE_CONFIG_H
+#	include <config.h>
+#else
+#	warning "config.h not found, package misconfigured."
+#	define PACKAGE "mdk"
+#	define VERSION "0.0"
+#endif 
+
+#ifdef HAVE_LOCALE_H
+#	include <locale.h>
+#endif
+
+#ifdef HAVE_GETTEXT
+#	include <libintl.h>
+#	define gettext_noop(String)	(String)
+#else
+#	include <intl/libintl.h>
+#endif 
+
+#define _(String) gettext (String)
+#define N_(String) gettext_noop (String)
+
+#include <glib.h>
+
+/* This function must be called before using the library */
+extern void 
+mix_init_lib (void);
+
+/* This function must be called for deallocating the lib resources
+   when it is no longer in use 
+*/
+extern void
+mix_release_lib (void);
+
+
+extern const char *MIX_GPL_LICENSE;
+
+
+#endif /* MIX_H */
+
diff --git a/mixlib/mix_code_file.c b/mixlib/mix_code_file.c
new file mode 100644
index 0000000..9bcd098
--- /dev/null
+++ b/mixlib/mix_code_file.c
@@ -0,0 +1,320 @@
+/* -*-c-*- -------------- mix_code_file.c :
+ * Implementation of the functions declared in mix_code_file.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+#include "mix.h"
+#include "xmix_io.h"
+#include "mix_code_file.h"
+
+/* mix_code_file_t type */
+static const gint32 SIGNATURE_ = 0xDEADBEEF;	/* release files */ 
+static const gint32 SIGNATURE_D_ = 0xBEEFDEAD;	/* debug files */
+
+#define IS_DEBUG_(file) ((file)->header.signature == SIGNATURE_D_)
+#define IS_RELEASE_(file) ((file)->header.signature == SIGNATURE_)
+
+
+typedef struct mix_cfheader_t mix_cfheader_t;
+struct mix_cfheader_t
+{
+  gint32 signature;
+  gint mj_ver;
+  gint mn_ver;
+  gint16 start;
+  size_t path_len;
+};
+
+struct mix_code_file_t 
+{
+  mix_file_t *file;			/* the underlying disk file */
+  mix_address_t address;		/* current address while reading */
+  mix_cfheader_t header;		/* file header */
+  gchar *source_path;			/* variable length part of the header*/
+  mix_symbol_table_t *symbol_table;	/* code files with debug info fill it*/
+};
+
+#define to_io_(cf)  MIX_IOCHANNEL (cf->file)
+
+/* Code files are lists of tagged words. A MIX_INS_TAG_ denotes
+ * that the word is an instruction, whose address is the next to
+ * the previous instruction's one, while a MIX_ADDR_TAG_ indicates
+ * that the word is a new address origin for the next instructions.
+ * The tags are stored as bit patterns in bit 31 of the mix word.
+ */
+#define MIX_ADDR_TAG_ (MIX_WORD_SIGN_BIT<<1)
+
+#define is_ins_(word) (((word)&MIX_ADDR_TAG_) == MIX_WORD_ZERO)
+#define is_addr_(word) (((word)&MIX_ADDR_TAG_) == MIX_ADDR_TAG_)
+#define tag_ins_(word) (word)
+#define tag_addr_(word) ((word)|MIX_ADDR_TAG_)
+#define extract_ins_(tagged) (tagged)
+#define extract_addr_(tagged) ((tagged)&MIX_SHORT_MAX)
+
+/* mix code files have a default extension (.mix) which is customizable */
+static const gchar *DEFEXT_ = NULL;
+
+const gchar *
+mix_code_file_get_defext (void)
+{
+  return DEFEXT_;
+}
+
+gboolean
+mix_code_file_set_defext (const gchar *ext)
+{
+  if (DEFEXT_ != NULL)  g_free ((void *)DEFEXT_);
+  DEFEXT_ =  (ext != NULL)? g_strdup (ext):NULL;
+  return (DEFEXT_ != NULL || ext == NULL);
+}
+
+/* create/destroy code files for read or write */
+static mix_code_file_t *
+mix_code_file_new_ (const gchar *name, mix_fmode_t mode)
+{
+  mix_code_file_t *result = g_new (mix_code_file_t, 1);
+  if ( result != NULL ) 
+    {
+      result->file = mix_file_new_with_def_ext (name, mode, DEFEXT_);
+      result->address = MIX_SHORT_ZERO;
+      result->symbol_table = NULL;
+    }
+  if ( result != NULL && result->file == NULL ) 
+    {
+      g_free (result);
+      result = NULL;
+    }
+  return result;
+}
+
+mix_code_file_t *
+mix_code_file_new_read (const gchar *name)
+{
+  mix_code_file_t *result = mix_code_file_new_ (name, mix_io_READ);
+  mix_cfheader_t *header;
+  FILE *file;
+  gboolean check; 
+  
+  if ( result == NULL ) 
+    return NULL;
+  
+  file = mix_file_to_FILE (result->file);
+  header = &(result->header);
+  check = fread (header, sizeof (mix_cfheader_t), 1, file);
+  
+  if ( check )
+    check = IS_RELEASE_ (result) || IS_DEBUG_ (result);
+  if ( check )
+    {/* a code file is compatible if its major version is
+	is the same as this package's and its minor version is <= */
+      gint major, minor;
+      sscanf (VERSION, "%d.%d", &major, &minor);
+      check = header->mj_ver == major && header->mn_ver <= minor;
+    }
+  if ( check )
+    {/* get source path */
+      result->source_path = g_strnfill (1 + header->path_len, '\0');
+      check =  result->source_path != NULL
+	&& fgets (result->source_path, 1 + header->path_len, file) != NULL;
+    }
+  if ( check && IS_DEBUG_ (result) )
+    {/* read symbol table */
+      result->symbol_table = mix_symbol_table_new_from_file (file);
+      check = result->symbol_table != NULL;
+    }
+  if ( !check )      
+    {
+      mix_code_file_delete (result);
+      return NULL;
+    }
+  return result;
+}
+
+mix_code_file_t *
+mix_code_file_new_write(const gchar *name, mix_address_t addr, 
+			const gchar *source_path, gboolean debug,
+			const mix_symbol_table_t *table)
+{
+  mix_code_file_t *result;
+  FILE *file;
+  gboolean check;
+  
+  result =  mix_code_file_new_ (name, mix_io_WRITE);
+  if ( result == NULL || ( file = mix_file_to_FILE (result->file) ) == NULL ) 
+    return NULL;
+  else if ( source_path != NULL )
+    {
+      result->source_path = g_strdup (source_path/*, MAX_PATH_LEN_*/);
+      if ( result->source_path == NULL ) 
+	{
+	  mix_code_file_delete (result);
+	  return NULL;
+	}
+    }
+  else
+    result->source_path = NULL;
+  
+  result->header.signature = debug? SIGNATURE_D_:SIGNATURE_;
+  sscanf (VERSION, "%d.%d", &result->header.mj_ver, &result->header.mn_ver);
+  result->header.start = (gint16) addr;
+  result->header.path_len = strlen (result->source_path);
+  check =  write_data_ (to_io_ (result), &result->header, 1);
+  if ( check && result->source_path != NULL )
+    check = fputs (result->source_path, file) != EOF;
+  if ( check && debug )
+    mix_symbol_table_print (table, MIX_SYM_LINE, file);
+  if ( !check )
+    {
+      mix_code_file_delete (result);
+      return NULL;
+    }
+  return result;
+}
+
+void
+mix_code_file_delete (mix_code_file_t *file) 
+{
+  g_return_if_fail (file != NULL);
+  mix_file_delete (file->file);
+  if ( file->source_path ) g_free (file->source_path);
+  g_free (file);
+}
+
+
+
+/* get general parameters from a code file */
+gboolean
+mix_code_file_is_debug (const mix_code_file_t *file)
+{
+  return (file == NULL ) ? FALSE : IS_DEBUG_ (file);
+}
+
+
+gint
+mix_code_file_major_version (const mix_code_file_t *file)
+{
+  g_return_val_if_fail (file != NULL, 0);
+  return file->header.mj_ver;
+}
+
+gint
+mix_code_file_minor_version (const mix_code_file_t *file)
+{
+  g_return_val_if_fail (file != NULL, 0);
+  return file->header.mn_ver;
+}
+
+mix_address_t
+mix_code_file_get_start_addr (const mix_code_file_t *file)
+{
+  g_return_val_if_fail (file != NULL, MIX_SHORT_ZERO);
+  return mix_short_new (file->header.start);
+}
+
+mix_symbol_table_t *
+mix_code_file_get_symbol_table(mix_code_file_t *file)
+{
+  mix_symbol_table_t *result = NULL;
+  g_return_val_if_fail (file != NULL, NULL);
+  result = file->symbol_table;
+  file->symbol_table = NULL;
+  return result;
+}
+
+/* read instructions from a code file */
+gboolean
+mix_code_file_is_eof (mix_code_file_t *file)
+{
+  return is_eof_ (to_io_ (file));
+}
+
+gboolean
+mix_code_file_get_ins (mix_code_file_t *file, mix_ins_desc_t *desc)
+{
+  mix_word_t next;
+  g_return_val_if_fail (file != NULL, FALSE);
+  g_return_val_if_fail (desc != NULL, FALSE);
+  while (TRUE) 
+    {
+      if ( ! mix_io_read_word_array (to_io_ (file), &next, 1) ) return FALSE;
+      if ( is_addr_ (next) )
+	file->address = extract_addr_ (next);
+      else if ( is_ins_ (next) ) 
+	{
+	  desc->ins = extract_ins_ (next);
+	  desc->address = (file->address)++;
+	  if ( IS_DEBUG_ (file) )
+	    {
+	      mix_short_t lineno;
+	      if ( !mix_io_read_short_array (to_io_ (file), &lineno, 1) )
+		return FALSE;
+	      desc->lineno = mix_short_magnitude (lineno);
+	    }
+	  else
+	    desc->lineno = 0;
+	  return TRUE;
+	} 
+      else
+	{
+	  g_assert_not_reached ();
+	  return FALSE;
+	}
+    };
+}
+
+/* Write instructions to a code file */
+gboolean
+mix_code_file_write_ins (mix_code_file_t *file, const mix_ins_desc_t *desc)
+{
+  g_return_val_if_fail (desc != NULL, FALSE);
+  return ( mix_code_file_set_address (file, desc->address) &&
+	   mix_code_file_write_next_ins (file, desc->ins, desc->lineno) );
+}
+
+gboolean
+mix_code_file_write_next_ins (mix_code_file_t *file, mix_word_t ins, 
+			      guint lineno)
+{
+  g_return_val_if_fail (file != NULL, FALSE);
+  if ( mix_io_write_word (to_io_ (file), tag_ins_ (ins)) 
+       && ( IS_RELEASE_ (file)
+	    || mix_io_write_short (to_io_ (file), mix_short_new (lineno)) ) 
+       )
+    {
+      ++(file->address);
+      return TRUE;
+    } 
+  else
+    return FALSE;
+}
+
+gboolean
+mix_code_file_set_address (mix_code_file_t *file, mix_address_t address)
+{
+  g_return_val_if_fail(file != NULL, FALSE);
+  if ( file->address != address ) {
+    if ( !mix_io_write_word (to_io_ (file),
+			     tag_addr_ (mix_short_to_word_fast (address))) )
+      return FALSE;
+    file->address = address;
+  }
+  return TRUE;
+}
+
+  
diff --git a/mixlib/mix_code_file.h b/mixlib/mix_code_file.h
new file mode 100644
index 0000000..34c0f21
--- /dev/null
+++ b/mixlib/mix_code_file.h
@@ -0,0 +1,102 @@
+/* -*-c-*- ---------------- mix_code_file.h :
+ * Declaration of mix_code_file_t, a file containing compiled mix 
+ * instructions.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIX_CODE_FILE_H
+#define MIX_CODE_FILE_H
+
+#include "mix_file.h"
+#include "mix_ins.h"
+#include "mix_symbol_table.h"
+
+/* mix_code_file_t type */
+typedef struct mix_code_file_t mix_code_file_t;
+
+/* instructions are loaded at specific memory addresses and related to
+   source line numbers
+*/
+typedef struct mix_ins_desc_t mix_ins_desc_t;
+struct mix_ins_desc_t 
+{
+  mix_word_t ins;		/* a mix instruction coded into a word */
+  mix_address_t address;	/* the address of this instruction */
+  guint lineno;			/* source file line no. */
+};
+
+/* mix code files have a default extension (.mix) which is customizable */
+extern const gchar *
+mix_code_file_get_defext(void);
+
+extern gboolean
+mix_code_file_set_defext(const gchar *ext);
+
+/* create/destroy code files for read or write */
+/* if -name- does not end with defext, it is automatically appended */
+extern mix_code_file_t *
+mix_code_file_new_read(const gchar *name);
+
+/* open a code file for write with/out debug information */
+extern mix_code_file_t *
+mix_code_file_new_write(const gchar *name, mix_address_t start,
+			const gchar *source_path, gboolean debug,
+			const mix_symbol_table_t *table);
+
+extern void
+mix_code_file_delete(mix_code_file_t *file);
+
+/* get general parameters from a code file */
+extern gboolean
+mix_code_file_is_debug(const mix_code_file_t *file);
+
+extern gint
+mix_code_file_major_version(const mix_code_file_t *file);
+
+extern gint
+mix_code_file_minor_version(const mix_code_file_t *file);
+
+extern mix_address_t
+mix_code_file_get_start_addr(const mix_code_file_t *file);
+
+extern mix_symbol_table_t *
+mix_code_file_get_symbol_table(mix_code_file_t *file);
+
+/* read instructions from a code file */
+extern gboolean
+mix_code_file_is_eof(mix_code_file_t *file);
+
+extern gboolean
+mix_code_file_get_ins(mix_code_file_t *file, mix_ins_desc_t *desc);
+
+/* write instructions to a code file */
+extern gboolean
+mix_code_file_write_ins(mix_code_file_t *file, const mix_ins_desc_t *desc);
+
+extern gboolean
+mix_code_file_write_next_ins(mix_code_file_t *file, mix_word_t ins, 
+			     guint lineno);
+
+extern gboolean
+mix_code_file_set_address(mix_code_file_t *file, mix_address_t address);
+
+
+#endif /* MIX_CODE_FILE_H */
+
diff --git a/mixlib/mix_device.c b/mixlib/mix_device.c
new file mode 100644
index 0000000..30fee7e
--- /dev/null
+++ b/mixlib/mix_device.c
@@ -0,0 +1,217 @@
+/* -*-c-*- -------------- mix_device.c :
+ * Implementation of the functions declared in mix_device.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#include "mix_file.h"
+#include "mix_device.h"
+
+/*
+  Actual definition of a mix device, which can be cast to
+  a mix file.
+*/
+struct mix_device_t 
+{
+  mix_iochannel_t *file;
+  mix_device_type_t type;
+};
+
+
+static const char *DEV_EXT_ = ".dev";
+
+static const char *DEF_NAMES_[] = {
+  "tape0", "tape1", "tape2", "tape3", "tape4", "tape5", "tape6", "tape7",
+  "disk0", "disk1", "disk2", "disk3", "disk4", "disk5", "disk6", "disk7",
+  "cardrd", "cardwr", "printer", "console", "paper"
+};
+
+static const size_t SIZES_[] = {
+  100, 100, 100, 100, 100, 100, 100, 100,
+  100, 100, 100, 100, 100, 100, 100, 100,
+  16, 16, 24, 14, 14
+};
+
+static const mix_device_mode_t MODES_[] = {
+  mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN,  
+  mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN,  
+  mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN,
+  mix_dev_BIN, mix_dev_CHAR, mix_dev_CHAR, mix_dev_CHAR, mix_dev_CHAR,
+  mix_dev_CHAR
+};
+
+static const mix_fmode_t FMODES_[] = {
+  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,
+  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,
+  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,
+  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,
+  mix_io_READ, mix_io_WRITE, mix_io_WRITE, mix_io_RDWRT, mix_io_WRITE
+};
+
+#define GET_CHANNEL_(dev) (dev->file)
+#define GET_FILE_(dev) ((mix_file_t *)(dev->file))
+
+mix_device_t *
+mix_device_new (mix_device_type_t type)
+{
+  mix_device_t *result = g_new (mix_device_t, 1);
+  g_return_val_if_fail (result != NULL, result);
+  result->type = type;
+  if (type != mix_dev_CONSOLE) {
+    result->file = MIX_IOCHANNEL(mix_file_new_with_def_ext (DEF_NAMES_[type],
+							    FMODES_[type],
+							    DEV_EXT_));
+  } else
+    result->file = mix_io_new (stdout);
+    
+  return result;
+}
+
+void
+mix_device_delete (mix_device_t *dev)
+{
+  if (dev != NULL)
+    {
+      if (dev->type != mix_dev_CONSOLE && GET_FILE_(dev) != NULL)
+	mix_file_delete (GET_FILE_(dev));
+      g_free (dev);
+    }
+}
+
+mix_device_t *
+mix_device_new_with_name (mix_device_type_t type, const gchar *name)
+{
+  mix_device_t *result = NULL;
+  g_return_val_if_fail (name != NULL, result);
+  result = g_new (mix_device_t, 1);  
+  g_return_val_if_fail (result != NULL, result);
+  result->type = type;
+  if (type != mix_dev_CONSOLE)
+    {
+      result->file = MIX_IOCHANNEL(mix_file_new_with_def_ext (name,
+							      FMODES_[type],
+							      DEV_EXT_));
+    }
+  else
+    {
+      result->file = mix_io_new (stdout);
+    }
+  return result;
+}
+
+const char *
+mix_device_get_name (mix_device_t *dev)
+{
+  g_return_val_if_fail (dev != NULL, NULL);
+  return mix_file_base_name(GET_FILE_(dev));
+}
+
+/*
+  Get the device block size
+*/
+size_t
+mix_device_block_size (mix_device_t *dev)
+{
+  g_return_val_if_fail (dev != NULL, 0);
+  return SIZES_[dev->type];
+}
+
+/*
+  Get the device io mode
+*/
+mix_device_mode_t
+mix_device_mode (mix_device_t *dev) 
+{
+  g_return_val_if_fail (dev != NULL, 0);
+  return MODES_[dev->type];
+}
+
+/*
+  Write a block to the device.
+*/
+gboolean
+mix_device_write (mix_device_t *dev, const mix_word_t *block) 
+{
+  gboolean result;
+  
+  g_return_val_if_fail (dev != NULL, FALSE);
+  g_return_val_if_fail (block != NULL, FALSE);
+  if (FMODES_[dev->type] == mix_io_READ) return FALSE;
+  if (MODES_[dev->type] == mix_dev_CHAR)
+    result = mix_io_write_word_array_as_char (GET_CHANNEL_ (dev),
+					      block, SIZES_[dev->type]);
+  else
+    result = mix_io_write_word_array (GET_CHANNEL_ (dev),
+				      block, SIZES_[dev->type]);
+  if (result && mix_device_mode(dev) == mix_dev_CHAR) 
+    putc ('\n', mix_io_to_FILE (GET_CHANNEL_ (dev)));
+  
+  return result;
+}
+
+gboolean
+mix_device_read (mix_device_t *dev, mix_word_t *block) 
+{
+  g_return_val_if_fail (dev != NULL, FALSE);
+  g_return_val_if_fail (block != NULL, FALSE);
+  if (FMODES_[dev->type] == mix_io_WRITE) return FALSE;
+  if (MODES_[dev->type] == mix_dev_CHAR)
+    return mix_io_read_word_array_as_char (GET_CHANNEL_ (dev),
+					   block, SIZES_[dev->type]);
+  else
+    return mix_io_read_word_array (GET_CHANNEL_ (dev),
+				   block, SIZES_[dev->type]);
+}
+
+gboolean
+mix_device_ioc (mix_device_t *dev, mix_short_t arg) 
+{
+  int m;
+  FILE *file;
+  
+  g_return_val_if_fail (dev != NULL, FALSE);
+
+  m = mix_short_magnitude(arg);
+  if (mix_short_is_negative(arg)) m = -m;
+  m *= sizeof (mix_word_t) * SIZES_[dev->type];
+  file = mix_io_to_FILE (GET_CHANNEL_(dev));
+  
+  if (dev->type >= mix_dev_TAPE_0 && dev->type <= mix_dev_TAPE_7)
+    {
+      if (m == 0) rewind (file);
+      else fseek (file, m, SEEK_CUR);
+    }
+  if (dev->type >= mix_dev_DISK_0 && dev->type <= mix_dev_DISK_7)
+    {
+      g_return_val_if_fail (m == 0, FALSE);
+      // position disk
+    }
+  if (dev->type == mix_dev_PAPER_TAPE)
+    {
+      g_return_val_if_fail (m == 0, FALSE);
+      rewind (file);
+    }
+  return TRUE;
+}
+
+gboolean
+mix_device_busy (mix_device_t *dev)
+{
+  return (dev != NULL && !mix_io_is_ready(GET_CHANNEL_(dev)));
+}
diff --git a/mixlib/mix_device.h b/mixlib/mix_device.h
new file mode 100644
index 0000000..c2e7edf
--- /dev/null
+++ b/mixlib/mix_device.h
@@ -0,0 +1,135 @@
+/* -*-c-*- ---------------- mix_device.h :
+ * Declaration of mix_device_t and associated methods.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIX_DEVICE_H
+#define MIX_DEVICE_H
+
+#include <stddef.h>
+#include "mix.h"
+#include "mix_types.h"
+
+/*
+  A mix device, which derives from mix_io_channel_t
+*/
+typedef struct mix_device_t mix_device_t;
+
+/*
+  The device type
+*/
+typedef enum {
+  mix_dev_TAPE_0,
+  mix_dev_TAPE_1,
+  mix_dev_TAPE_2,
+  mix_dev_TAPE_3,
+  mix_dev_TAPE_4,
+  mix_dev_TAPE_5,
+  mix_dev_TAPE_6,
+  mix_dev_TAPE_7,
+  mix_dev_DISK_0,
+  mix_dev_DISK_1,
+  mix_dev_DISK_2,
+  mix_dev_DISK_3,
+  mix_dev_DISK_4,
+  mix_dev_DISK_5,
+  mix_dev_DISK_6,
+  mix_dev_DISK_7,
+  mix_dev_CARD_RD,
+  mix_dev_CARD_WR,
+  mix_dev_PRINTER,
+  mix_dev_CONSOLE,
+  mix_dev_PAPER_TAPE
+} mix_device_type_t;
+
+/*
+  The device io mode
+*/
+typedef enum {
+  mix_dev_BIN,
+  mix_dev_CHAR
+} mix_device_mode_t;
+
+/*
+  Create a new device with default name and given type.
+*/
+extern mix_device_t *
+mix_device_new (mix_device_type_t type);
+
+/*
+  Create a new device with a given type and name.
+*/
+extern mix_device_t *
+mix_device_new_with_name (mix_device_type_t type, const gchar *name);
+
+/*
+  Delete a device.
+*/
+extern void
+mix_device_delete(mix_device_t *dev);
+
+/*
+  Get a device name
+*/
+extern const char *
+mix_device_get_name (mix_device_t *dev);
+
+/*
+  Get the device block size
+*/
+extern size_t
+mix_device_block_size (mix_device_t *dev);
+
+/*
+  Get the device io mode
+*/
+extern mix_device_mode_t
+mix_device_mode (mix_device_t *dev);
+
+/*
+  Write a block to the device.
+*/
+extern gboolean
+mix_device_write (mix_device_t *dev, const mix_word_t *block);
+
+/*
+  Read a block from the device.
+*/
+extern gboolean
+mix_device_read (mix_device_t *dev, mix_word_t *block);
+
+/*
+  Perform an io control operation on the device.
+  The parameter _arg_ is the operation's argument:
+   0- rewind to beginning
+   <0 - rewind the given number of blocks
+   >0 - skip forward the given number of blocks
+*/
+extern gboolean
+mix_device_ioc (mix_device_t *dev, mix_short_t arg);
+
+/*
+  Check if a device is busy
+*/
+extern gboolean
+mix_device_busy (mix_device_t *dev);
+
+#endif /* MIX_DEVICE_H */
+
diff --git a/mixlib/mix_file.c b/mixlib/mix_file.c
new file mode 100644
index 0000000..45d45e0
--- /dev/null
+++ b/mixlib/mix_file.c
@@ -0,0 +1,142 @@
+/* -*-c-*- -------------- mix_file.c :
+ * Implementation of the functions declared in mix_file.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#include "xmix_io.h"
+#include "mix_file.h"
+
+const gchar *MIX_SRC_DEFEXT = ".mixal", 
+  *MIX_LIST_DEFEXT = ".mls", *MIX_CODE_DEFEXT = ".mix";
+
+/* file names completions */
+#define needs_completion_(name,defext) \
+  ( strcmp(name + strlen(name) - strlen(defext), defext) != 0 )
+
+#define add_completion_(name, defext) \
+  g_strconcat(name, defext, NULL)
+
+/* The actual definition of mix_file_t */
+struct mix_file_t 
+{
+  mix_iochannel_t parent;
+  gchar *base_name;
+  gchar *ext;
+};
+
+/* Creation/destruction of files */
+static mix_file_t *
+open_file_(const gchar *name, mix_fmode_t mode)
+{
+  mix_file_t *result;
+  FILE *file;
+  
+  file = fopen(name, fmode_to_type_(mode));
+  if ( file == NULL ) return NULL;
+  result = g_new(mix_file_t, 1);
+  if ( result == NULL )
+    {
+      fclose(file);
+      return NULL;
+    }
+  io_init_from_file_(MIX_IOCHANNEL(result), file);
+  return result;
+}
+  
+mix_file_t *
+mix_file_new(const gchar *name, mix_fmode_t mode)
+{
+  mix_file_t *result;
+  gchar *bname;
+
+  if ( name == NULL ) return NULL;
+  bname = g_strdup(name);
+  if ( bname == NULL ) return NULL;
+  result = open_file_(name, mode);
+  if ( result == NULL )
+    {
+      g_free(bname);
+      return NULL;
+    }
+  result->base_name = bname;
+  result->ext = NULL;
+  return result;
+}
+
+/* creates a file adding to its name the defext if missing */
+mix_file_t *
+mix_file_new_with_def_ext(const gchar *name, mix_fmode_t mode, 
+			  const gchar *defext)
+{
+  const gchar *real_name;
+  mix_file_t *result;
+  
+  if ( name == NULL ) return NULL;
+  if ( defext == NULL ) return mix_file_new(name, mode);
+  real_name =  needs_completion_(name, defext) ? 
+    add_completion_(name, defext) : name;
+  result = open_file_(real_name, mode);
+  if ( real_name != name ) g_free((void *)real_name);
+  if ( result  == NULL ) return NULL;
+  result->ext = g_strdup(defext);
+  if ( needs_completion_(name, defext) )
+    result->base_name = g_strdup(name);
+  else
+    result->base_name = g_strndup(name, strlen(name) - strlen(defext));
+  if ( result->ext == NULL || result->base_name == NULL )
+    {
+      mix_file_delete(result);
+      return NULL;
+    }
+  return result;
+}
+
+void
+mix_file_delete(mix_file_t *file)
+{
+  g_return_if_fail(file != NULL);
+  io_close_(MIX_IOCHANNEL(file));
+  if (file->base_name) g_free(file->base_name);
+  if (file->ext) g_free(file->ext);
+  g_free(file);
+}
+
+/* convert to a standard FILE */
+extern FILE *
+mix_file_to_FILE(const mix_file_t *file)
+{
+  if ( file == NULL ) return NULL;
+  return io_get_FILE_(file);
+}
+
+/* Get the base name and extension of file */
+const gchar *
+mix_file_base_name(const mix_file_t *file)
+{
+  g_return_val_if_fail(file != NULL, NULL);
+  return file->base_name;
+}
+
+const gchar *
+mix_file_extension(const mix_file_t *file)
+{
+  g_return_val_if_fail(file != NULL, NULL);
+  return file->ext;
+}
diff --git a/mixlib/mix_file.h b/mixlib/mix_file.h
new file mode 100644
index 0000000..5be6717
--- /dev/null
+++ b/mixlib/mix_file.h
@@ -0,0 +1,61 @@
+/* -*-c-*- ---------------- mix_file.h :
+ * Declarations for the mix_file_t type.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIX_FILE_H
+#define MIX_FILE_H
+
+#include "mix_io.h"
+
+/* The mix_file_t type, deriving from mix_iochannel_t and 
+   representing a disk file 
+*/
+typedef struct mix_file_t mix_file_t;
+
+/* Creation/destruction of files */
+extern mix_file_t *
+mix_file_new(const gchar *name, mix_fmode_t mode);
+
+/* creates a file adding to its name the defext if missing */
+extern mix_file_t *
+mix_file_new_with_def_ext(const gchar *name, mix_fmode_t mode, 
+			  const gchar *defext);
+
+extern void
+mix_file_delete(mix_file_t *file);
+
+/* convert to a standard FILE */
+extern FILE *
+mix_file_to_FILE(const mix_file_t *file);
+
+/* standard default extensions */
+extern const gchar *MIX_SRC_DEFEXT, *MIX_LIST_DEFEXT, *MIX_CODE_DEFEXT;
+
+/* Get the base name and extension of file */
+extern const gchar *
+mix_file_base_name(const mix_file_t *file);
+
+extern const gchar *
+mix_file_extension(const mix_file_t *file);
+
+
+#endif /* MIX_FILE_H */
+
diff --git a/mixlib/mix_ins.c b/mixlib/mix_ins.c
new file mode 100644
index 0000000..c5fcaf7
--- /dev/null
+++ b/mixlib/mix_ins.c
@@ -0,0 +1,258 @@
+/* -*-c-*- ------------------ mix_ins.c :
+ * Implementation of the functions declared in mix_ins.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 1999 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+#include "mix_ins.h"
+
+/* -------------------------------------> MOVE to VM
+static mix_time_t interlock_time_ = 0;
+static const mix_time_t exec_times_[] = {
+  1, 2, 2, 10, 12, 10, 2, 1, 
+  2, 2, 2, 2 ,  2,  2, 2, 2,
+  2, 2, 2, 2 ,  2,  2, 2, 2,
+  2, 2, 2, 2 ,  2,  2, 2, 2,
+  2, 2, 1, 1,   1,  1, 1, 1,
+  1, 1, 1, 1,   1,  1, 1, 1,
+  1, 1, 1, 1,   1,  1, 1, 1,
+  2, 2, 2, 2 ,  2,  2, 2, 2
+};
+------------------------------------------------------*/
+  
+
+
+struct mix_ins_desc_ 
+{
+  mix_opcode_t opcode;
+  mix_fspec_t  def_fspec;
+  const gchar  *string_rep;
+  gboolean is_ext;
+};
+
+#define IDES_(c,f,s) {c,f,#s,FALSE}
+#define IDESX_(c,f,s) {c,f,#s,TRUE}
+
+static const struct mix_ins_desc_ id_to_desc_[] =  {
+  IDES_(0,0,NOP), IDES_(1,5,ADD), IDES_(2,5,SUB), IDES_(3,5,MUL),
+  IDES_(4,5,DIV), 
+  IDESX_(5,0,NUM), IDESX_(5,1,CHAR), IDESX_(5,2,HLT),  
+  IDESX_(6,0,SLA), IDESX_(6,1,SRA), IDESX_(6,2,SLAX), IDESX_(6,3,SRAX), 
+  IDESX_(6,4,SLC), IDESX_(6,5,SRC), 
+  IDES_(7,1,MOVE), IDES_(8,5,LDA), IDES_(9,5,LD1), IDES_(10,5,LD2),
+  IDES_(11,5,LD3), IDES_(12,5,LD4), IDES_(13,5,LD5), 
+  IDES_(14,5,LD6), IDES_(15,5,LDX), IDES_(16,5,LDAN), IDES_(17,5,LD1N), 
+  IDES_(18,5,LD2N), IDES_(19,5,LD3N), IDES_(20,5,LD4N),
+  IDES_(21,5,LD5N), IDES_(22,5,LD6N), IDES_(23,5,LDXN), 
+  IDES_(24,5,STA), IDES_(25,5,ST1), IDES_(26,5,ST2), IDES_(27,5,ST3), 
+  IDES_(28,5,ST4), IDES_(29,5,ST5), IDES_(30,5,ST6), IDES_(31,5,STX), 
+  IDES_(32,2,STJ), IDES_(33,5,STZ), IDES_(34,0,JBUS), IDES_(35,0,IOC), 
+  IDES_(36,0,IN), IDES_(37,0,OUT), IDES_(38,0,JRED), 
+  IDESX_(39,0,JMP), IDESX_(39,1,JSJ), IDESX_(39,2,JOV), IDESX_(39,3,JNOV), 
+  IDESX_(39,4,JL), IDESX_(39,5,JE), IDESX_(39,6,JG), IDESX_(39,7,JGE),
+  IDESX_(39,8,JNE), IDESX_(39,9,JLE),
+  IDESX_(40,0,JAN), IDESX_(40,1,JAZ), IDESX_(40,2,JAP), IDESX_(40,3,JANN), 
+  IDESX_(40,4,JANZ), IDESX_(40,5,JANP),
+  IDESX_(41,0,J1N), IDESX_(41,1,J1Z), IDESX_(41,2,J1P), IDESX_(41,3,J1NN), 
+  IDESX_(41,4,J1NZ), IDESX_(41,5,J1NP),
+  IDESX_(42,0,J2N), IDESX_(42,1,J2Z), IDESX_(42,2,J2P), IDESX_(42,3,J2NN), 
+  IDESX_(42,4,J2NZ), IDESX_(42,5,J2NP),
+  IDESX_(43,0,J3N), IDESX_(43,1,J3Z), IDESX_(43,2,J3P), IDESX_(43,3,J3NN), 
+  IDESX_(43,4,J3NZ), IDESX_(43,5,J3NP),
+  IDESX_(44,0,J4N), IDESX_(44,1,J4Z), IDESX_(44,2,J4P), IDESX_(44,3,J4NN), 
+  IDESX_(44,4,J4NZ), IDESX_(44,5,J4NP),
+  IDESX_(45,0,J5N), IDESX_(45,1,J5Z), IDESX_(45,2,J5P), IDESX_(45,3,J5NN), 
+  IDESX_(45,4,J5NZ), IDESX_(45,5,J5NP),
+  IDESX_(46,0,J6N), IDESX_(46,1,J6Z), IDESX_(46,2,J6P), IDESX_(46,3,J6NN), 
+  IDESX_(46,4,J6NZ), IDESX_(46,5,J6NP),
+  IDESX_(47,0,JXN), IDESX_(47,1,JXZ), IDESX_(47,2,JXP), IDESX_(47,3,JXNN), 
+  IDESX_(47,4,JXNZ), IDESX_(47,5,JXNP),
+  IDESX_(48,0,INCA), IDESX_(48,1,DECA), IDESX_(48,2,ENTA), IDESX_(48,3,ENNA), 
+  IDESX_(49,0,INC1), IDESX_(49,1,DEC1), IDESX_(49,2,ENT1), IDESX_(49,3,ENN1),
+  IDESX_(50,0,INC2), IDESX_(50,1,DEC2), IDESX_(50,2,ENT2), IDESX_(50,3,ENN2),
+  IDESX_(51,0,INC3), IDESX_(51,1,DEC3), IDESX_(51,2,ENT3), IDESX_(51,3,ENN3),
+  IDESX_(52,0,INC4), IDESX_(52,1,DEC4), IDESX_(52,2,ENT4), IDESX_(52,3,ENN4), 
+  IDESX_(53,0,INC5), IDESX_(53,1,DEC5), IDESX_(53,2,ENT5), IDESX_(53,3,ENN5), 
+  IDESX_(54,0,INC6), IDESX_(54,1,DEC6), IDESX_(54,2,ENT6), IDESX_(54,3,ENN6), 
+  IDESX_(55,0,INCX), IDESX_(55,1,DECX), IDESX_(55,2,ENTX), IDESX_(55,3,ENNX), 
+  IDES_(56,5,CMPA), IDES_(57,5,CMP1), IDES_(58,5,CMP2), IDES_(59,5,CMP3), 
+  IDES_(60,5,CMP4), IDES_(61,5,CMP5), IDES_(62,5,CMP6), IDES_(63,5,CMPX)
+};
+
+static const gsize ID_TO_DESC_SIZE_= 
+                   sizeof(id_to_desc_)/sizeof(id_to_desc_[0]);
+
+/* To look for the mix_ins_id corresponding to a pair (fspec,opcode)
+   we use an array indexed by opcode with values 
+   (initial_ins, final_ins - initial_ins)
+*/
+struct mix_opcode_desc_ 
+{
+  mix_ins_id_t init_id;
+  guchar       inc; /* when inc == 0, the id does not depend on fspec */
+};
+
+static struct mix_opcode_desc_ opcode_to_id_[MIX_BYTE_MAX + 1];
+
+/* a hash table mapping strings to mix_ins_id's */
+static GHashTable *string_to_id_ = NULL;
+
+void
+mix_init_ins(void) 
+{
+  guint k;
+  g_assert(ID_TO_DESC_SIZE_ == mix_INVALID_INS);
+  
+  for ( k = 0; k < MIX_BYTE_MAX + 1; ++k )
+    {
+      opcode_to_id_[k].init_id = mix_INVALID_INS;
+      opcode_to_id_[k].inc = 0;
+    }
+  
+  for ( k = 0; k < ID_TO_DESC_SIZE_; ++k )
+    {
+      if ( opcode_to_id_[id_to_desc_[k].opcode].init_id == mix_INVALID_INS )
+	opcode_to_id_[id_to_desc_[k].opcode].init_id = k;
+      else
+	++opcode_to_id_[id_to_desc_[k].opcode].inc;
+    }
+
+  if ( string_to_id_ == NULL )
+    {
+      string_to_id_ = g_hash_table_new(g_str_hash, g_str_equal);
+      for ( k = 0; k < ID_TO_DESC_SIZE_; ++k)
+	g_hash_table_insert(string_to_id_, (gpointer)id_to_desc_[k].string_rep,
+			    GUINT_TO_POINTER(k));
+    }
+  
+}
+
+void
+mix_release_ins(void)
+{
+  g_hash_table_destroy(string_to_id_);
+}
+
+/* Conversions between words and ins */
+mix_word_t
+mix_ins_to_word(const mix_ins_t *ins)
+{
+  g_return_val_if_fail(ins != NULL, MIX_WORD_ZERO);
+  return  (mix_word_t)((ins->address<<18)|
+		       ((ins->index&7)<<12)|(ins->fspec<<6)|(ins->opcode));
+}
+
+mix_ins_id_t
+mix_word_to_ins(mix_word_t word, mix_ins_t *ins)
+{
+  mix_ins_id_t result = mix_get_ins_id(mix_get_ins_opcode(word),
+				       mix_get_ins_fspec(word));
+  		       
+  g_return_val_if_fail(ins != NULL, result);
+  mix_word_to_ins_uncheck(word,*ins);
+  return result;
+}
+
+/* Getting ins parameters */
+mix_opcode_t
+mix_get_opcode_from_id(mix_ins_id_t id)
+{
+  g_return_val_if_fail(id < ID_TO_DESC_SIZE_, MIX_BYTE_ZERO);
+  return id_to_desc_[id].opcode;
+}
+
+gboolean
+mix_ins_id_is_extended(mix_ins_id_t id)
+{
+  g_return_val_if_fail(id < ID_TO_DESC_SIZE_, FALSE);
+  return id_to_desc_[id].is_ext;
+}
+
+
+mix_fspec_t
+mix_get_fspec_from_id(mix_ins_id_t id)
+{
+  g_return_val_if_fail(id < ID_TO_DESC_SIZE_, MIX_BYTE_ZERO);
+  return id_to_desc_[id].def_fspec;
+}
+
+
+const gchar * 
+mix_get_string_from_id(mix_ins_id_t id)
+{
+  g_return_val_if_fail(id < ID_TO_DESC_SIZE_, NULL);
+  return id_to_desc_[id].string_rep;
+}
+
+mix_ins_id_t
+mix_get_id_from_string(const gchar *name)
+{
+  gpointer key, value;
+  if ( !g_hash_table_lookup_extended(string_to_id_, (gpointer)name,
+				     &key, &value) )
+    return mix_INVALID_INS;
+  return (mix_ins_id_t)GPOINTER_TO_UINT(value);
+}
+
+
+mix_ins_id_t
+mix_get_ins_id(mix_opcode_t code, mix_fspec_t fspec)
+{
+  if ( opcode_to_id_[code].inc == 0 )
+    return opcode_to_id_[code].init_id;
+  else if ( opcode_to_id_[code].inc < fspec )
+    return mix_INVALID_INS;
+  else
+    return (opcode_to_id_[code].init_id + fspec);
+}
+
+/* Printable representation */
+extern gchar * /* this pointer must be freed by caller */
+mix_ins_to_string(const mix_ins_t *ins)
+{
+  gboolean needs_f;
+  gchar *result;
+  mix_ins_id_t id;
+  
+  g_return_val_if_fail(ins != NULL, NULL);
+  id = mix_ins_id_from_ins(*ins);
+  needs_f = ins->fspec != id_to_desc_[id].def_fspec;
+  if ( needs_f ) 
+    result =  g_strdup_printf("%s\t%s%d,%d(%d:%d)",  
+			      mix_get_string_from_id(id),
+			      mix_short_is_negative(ins->address)?"-":"",
+			      mix_short_magnitude(ins->address), ins->index, 
+			      mix_fspec_left(ins->fspec), 
+			      mix_fspec_right(ins->fspec));
+  else
+    result =  g_strdup_printf("%s\t%s%d,%d", mix_get_string_from_id(id),
+			      mix_short_is_negative(ins->address)?"-":"",
+			      mix_short_magnitude(ins->address), ins->index);
+  return result;
+}
+
+void
+mix_ins_print(const mix_ins_t *ins)
+{
+  g_return_if_fail(ins != NULL);
+  g_print(mix_get_string_from_id(mix_ins_id_from_ins(*ins)));
+  g_print(" %s%d,%d(%d:%d)", mix_short_is_negative(ins->address)?"-":"+",
+	  mix_short_magnitude(ins->address), ins->index, 
+	  mix_fspec_left(ins->fspec), mix_fspec_right(ins->fspec));
+}
+
diff --git a/mixlib/mix_ins.h b/mixlib/mix_ins.h
new file mode 100644
index 0000000..5915a19
--- /dev/null
+++ b/mixlib/mix_ins.h
@@ -0,0 +1,192 @@
+/* -*-c-*- -------------------- mix_ins.h:
+ * This file declares types and functions for manipulating MIX
+ * instructions
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIX_INS_H
+#define MIX_INS_H
+
+#include "mix_types.h"
+
+
+/* Initialise and free mix_ins data */
+extern void
+mix_init_ins(void);
+
+extern void
+mix_release_ins(void);
+
+/* A MIX instruction is made up of address, index, fspec and op_code */
+
+/*-- Address field: contains two bytes */
+typedef mix_short_t  mix_address_t;
+
+/*-- Index field: a value between 0 and 6 */
+typedef enum { 
+  mix_I0, mix_I1, mix_I2, mix_I3, mix_I4, mix_I5, mix_I6 } mix_index_t;
+
+/*-- Instruction id: enumeration of MIX instruction set */
+typedef enum {
+  mix_NOP,  mix_ADD, mix_SUB, mix_MUL, mix_DIV, 
+  mix_NUM, mix_CHAR, mix_HLT,  
+  mix_SLA, mix_SRA, mix_SLAX, mix_SRAX, mix_SLC, mix_SRC, 
+  mix_MOVE, mix_LDA, mix_LD1, mix_LD2, mix_LD3, mix_LD4, mix_LD5, 
+  mix_LD6,  mix_LDX, mix_LDAN, mix_LD1N, mix_LD2N, mix_LD3N, mix_LD4N,
+  mix_LD5N, mix_LD6N, mix_LDXN, mix_STA, mix_ST1, mix_ST2, mix_ST3, mix_ST4, 
+  mix_ST5, mix_ST6, mix_STX, mix_STJ, mix_STZ, mix_JBUS, mix_IOC, mix_IN, 
+  mix_OUT, mix_JRED, 
+  mix_JMP, mix_JSJ, mix_JOV, mix_JNOV, mix_JL, mix_JE, mix_JG, mix_JGE,
+  mix_JNE, mix_JLE,
+  mix_JAN, mix_JAZ, mix_JAP, mix_JANN, mix_JANZ, mix_JANP, 
+  mix_J1N, mix_J1Z, mix_J1P, mix_J1NN, mix_J1NZ, mix_J1NP,
+  mix_J2N, mix_J2Z, mix_J2P, mix_J2NN, mix_J2NZ, mix_J2NP,
+  mix_J3N, mix_J3Z, mix_J3P, mix_J3NN, mix_J3NZ, mix_J3NP,
+  mix_J4N, mix_J4Z, mix_J4P, mix_J4NN, mix_J4NZ, mix_J4NP,
+  mix_J5N, mix_J5Z, mix_J5P, mix_J5NN, mix_J5NZ, mix_J5NP,
+  mix_J6N, mix_J6Z, mix_J6P, mix_J6NN, mix_J6NZ, mix_J6NP,
+  mix_JXN, mix_JXZ, mix_JXP, mix_JXNN, mix_JXNZ, mix_JXNP, 
+  mix_INCA, mix_DECA, mix_ENTA, mix_ENNA, 
+  mix_INC1, mix_DEC1, mix_ENT1, mix_ENN1,
+  mix_INC2, mix_DEC2, mix_ENT2, mix_ENN2,
+  mix_INC3, mix_DEC3, mix_ENT3, mix_ENN3,
+  mix_INC4, mix_DEC4, mix_ENT4, mix_ENN4, 
+  mix_INC5, mix_DEC5, mix_ENT5, mix_ENN5, 
+  mix_INC6, mix_DEC6, mix_ENT6, mix_ENN6, 
+  mix_INCX, mix_DECX, mix_ENTX, mix_ENNX, 
+  mix_CMPA, mix_CMP1, mix_CMP2, mix_CMP3, mix_CMP4, 
+  mix_CMP5, mix_CMP6, mix_CMPX, mix_INVALID_INS
+} mix_ins_id_t;
+
+/* each one of the above id's has associated an opcode, a default
+   fspec and a string representation */
+/* the opcode fits in a byte */
+typedef mix_byte_t mix_opcode_t;
+
+/* labels for each opcode */
+enum {
+  mix_opNOP = 0, mix_opADD, mix_opSUB, mix_opMUL, mix_opDIV, 
+  mix_opSPC, mix_opSLx, mix_opMOVE, 
+  mix_opLDA, mix_opLD1, mix_opLD2, mix_opLD3, mix_opLD4, mix_opLD5, 
+  mix_opLD6, mix_opLDX, mix_opLDAN, mix_opLD1N, mix_opLD2N, mix_opLD3N, 
+  mix_opLD4N, mix_opLD5N, mix_opLD6N, mix_opLDXN, 
+  mix_opSTA, mix_opST1, mix_opST2, mix_opST3, mix_opST4, 
+  mix_opST5, mix_opST6, mix_opSTX, mix_opSTJ, mix_opSTZ, 
+  mix_opJBUS, mix_opIOC, mix_opIN, mix_opOUT, mix_opJRED, 
+  mix_opJMP, mix_opJAx, mix_opJ1x, mix_opJ2x, mix_opJ3x, 
+  mix_opJ4x, mix_opJ5x, mix_opJ6x, mix_opJXx,
+  mix_opINCA, mix_opINC1, mix_opINC2, mix_opINC3, 
+  mix_opINC4, mix_opINC5, mix_opINC6, mix_opINCX,
+  mix_opCMPA, mix_opCMP1, mix_opCMP2, mix_opCMP3, mix_opCMP4, 
+  mix_opCMP5, mix_opCMP6, mix_opCMPX
+};
+ 
+extern mix_opcode_t
+mix_get_opcode_from_id(mix_ins_id_t id);
+
+extern mix_fspec_t
+mix_get_fspec_from_id(mix_ins_id_t id);
+
+/* For extended instructions, both the opcode and fspec determine
+   the id (i.e., an explicit fspec cannot be used)
+*/
+extern gboolean
+mix_ins_id_is_extended(mix_ins_id_t id);
+
+extern const gchar * 
+mix_get_string_from_id(mix_ins_id_t id);
+
+extern mix_ins_id_t
+mix_get_id_from_string(const gchar *name);
+
+extern mix_ins_id_t
+mix_get_ins_id(mix_opcode_t code, mix_fspec_t fspec);
+
+
+/*--  MIX instruction type */
+typedef struct mix_ins_t mix_ins_t;
+struct mix_ins_t 
+{
+  mix_address_t address;
+  mix_index_t   index;
+  mix_fspec_t   fspec;
+  mix_opcode_t  opcode;
+};
+
+#define mix_ins_fill_from_id(ins,id)		\
+   do {						\
+     (ins).opcode = mix_get_opcode_from_id(id);	\
+     (ins).fspec = mix_get_fspec_from_id(id);	\
+   } while(FALSE)
+
+
+/* A mix ins can be codified into a word */
+extern mix_word_t
+mix_ins_to_word(const mix_ins_t *ins);
+
+extern mix_ins_id_t
+mix_word_to_ins(mix_word_t w, mix_ins_t *ins);
+
+#define mix_word_set_address(word,addr) (word) |= ((addr)<<18) 
+
+/* decompose an instruction codified in a word into its parts */
+#define mix_get_ins_address(word) ((mix_address_t)((word)>>18))
+#define mix_get_ins_index(word)   ((mix_index_t)(((word)>>12)&7))
+#define mix_get_ins_fspec(word)   ((mix_fspec_t)(mix_byte_new((word)>>6)))
+#define mix_get_ins_opcode(word)  ((mix_opcode_t)(mix_byte_new(word)))
+
+/* unchecked versions for speed */
+#define mix_ins_to_word_uncheck(ins)					\
+ (mix_word_t)(((ins).address<<18)|					\
+	      (((ins).index&7)<<12)|((ins).fspec<<6)|((ins).opcode))
+
+#define mix_word_to_ins_uncheck(word,ins)	\
+  do {						\
+    (ins).address = mix_get_ins_address(word);	\
+    (ins).index = mix_get_ins_index(word);	\
+    (ins).fspec = mix_get_ins_fspec(word);	\
+    (ins).opcode = mix_get_ins_opcode(word);	\
+  } while(FALSE)
+
+#define mix_ins_id_from_ins(ins)  mix_get_ins_id((ins).opcode,(ins).fspec)
+
+
+/* Printable representation */
+extern gchar * /* this pointer must be freed by caller */
+mix_ins_to_string(const mix_ins_t *ins);
+
+extern void
+mix_ins_print(const mix_ins_t *ins);
+
+
+
+/* A MIX ins has an associated execution time */
+/* Initialise mix_ins data providing an interlock time for I/O devices */
+/* --------------------------------------> MOVE to VM
+typedef guint mix_time_t;
+
+extern void
+mix_init_ins_with_interlock_time(mix_time_t t);
+
+extern mix_time_t  
+mix_ins_exec_time(const mix_ins_t *ins);
+*/
+
+#endif /* MIX_INS_H */
diff --git a/mixlib/mix_io.c b/mixlib/mix_io.c
new file mode 100644
index 0000000..9014902
--- /dev/null
+++ b/mixlib/mix_io.c
@@ -0,0 +1,220 @@
+/* -*-c-*- --------------- mix_io.c :
+ * Implementation of the functions declared in mix_io.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#include "xmix_io.h"
+
+mix_iochannel_t *
+mix_io_new (FILE *file)
+{
+  mix_iochannel_t *result;
+  g_return_val_if_fail (file != NULL, NULL);
+  result = g_new (mix_iochannel_t, 1);
+  g_return_val_if_fail (result != NULL, NULL);
+  result->file = file;
+  return result;
+}
+
+void
+mix_io_delete (mix_iochannel_t *ch)
+{
+  if (ch != NULL)
+    {
+      fclose (ch->file);
+      g_free (ch);
+    }
+}
+
+FILE *
+mix_io_to_FILE (mix_iochannel_t *ioc)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  return ioc->file;
+}
+
+gboolean
+mix_io_eof (mix_iochannel_t *ioc)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  return is_eof_ (ioc);
+}
+
+gboolean
+mix_io_is_ready (mix_iochannel_t *ioc)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  return is_ready_ (ioc);
+}
+
+gboolean
+mix_io_write_byte (mix_iochannel_t *ioc, mix_byte_t b)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  return write_data_ (ioc, &b, 1);
+}
+
+gboolean
+mix_io_write_byte_array (mix_iochannel_t *ioc, const mix_byte_t *b,
+			 size_t s)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  g_return_val_if_fail (b != NULL, FALSE);
+  return write_data_ (ioc, b, s);
+}
+
+
+mix_byte_t
+mix_io_read_byte (mix_iochannel_t *ioc)
+{
+  mix_byte_t result = MIX_BYTE_ZERO;
+  g_return_val_if_fail (ioc != NULL, result);
+  g_return_val_if_fail (read_data_ (ioc, &result, 1), MIX_BYTE_ZERO);
+  return result;
+}
+  
+gboolean
+mix_io_read_byte_array (mix_iochannel_t *ioc, mix_byte_t *b, size_t s)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  g_return_val_if_fail (b != NULL, FALSE);
+  return read_data_ (ioc, b, s);
+}
+
+gboolean
+mix_io_write_word (mix_iochannel_t *ioc, mix_word_t w)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  return write_data_ (ioc, &w, 1);
+}
+
+gboolean
+mix_io_write_word_array (mix_iochannel_t *ioc, const mix_word_t *w,
+			 size_t s)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  g_return_val_if_fail (w != NULL, FALSE);
+  return write_data_ (ioc, &w, s);
+}
+
+mix_word_t
+mix_io_read_word (mix_iochannel_t *ioc)
+{
+  mix_word_t result = MIX_WORD_ZERO;
+  g_return_val_if_fail (ioc != NULL, result);
+  g_return_val_if_fail (read_data_ (ioc, &result, 1), MIX_WORD_ZERO);
+  return result;
+}
+
+gboolean
+mix_io_read_word_array (mix_iochannel_t *ioc, mix_word_t *w, size_t s)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  g_return_val_if_fail (w != NULL, FALSE);
+  return read_data_ (ioc, w, s);
+}
+
+gboolean
+mix_io_write_short (mix_iochannel_t *ioc, mix_short_t w)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  return write_data_ (ioc, &w, 1);
+}
+
+gboolean
+mix_io_write_short_array (mix_iochannel_t *ioc, const mix_short_t *w,
+			  size_t s)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  g_return_val_if_fail (w != NULL, FALSE);
+  return write_data_ (ioc, &w, s);
+}
+
+mix_short_t
+mix_io_read_short (mix_iochannel_t *ioc)
+{
+  mix_short_t result = MIX_SHORT_ZERO;
+  g_return_val_if_fail (ioc != NULL, result);
+  g_return_val_if_fail (read_data_ (ioc, &result, 1), MIX_SHORT_ZERO);
+  return result;
+}
+
+gboolean
+mix_io_read_short_array (mix_iochannel_t *ioc, mix_short_t *w, size_t s)
+{
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  g_return_val_if_fail (w != NULL, FALSE);
+  return read_data_ (ioc, w, s);
+}
+
+gboolean
+mix_io_write_char (mix_iochannel_t *ioc, mix_char_t c)
+{
+  guchar value = mix_char_to_ascii (c);
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  return write_data_ (ioc, &value, 1);
+}
+
+mix_char_t
+mix_io_read_char (mix_iochannel_t *ioc)
+{
+  guchar value;
+  g_return_val_if_fail (ioc != NULL, MIX_CHAR_MAX);
+  g_return_val_if_fail (read_data_ (ioc, &value, 1), MIX_CHAR_MAX);
+  return mix_ascii_to_char (value);
+}
+
+gboolean
+mix_io_write_word_array_as_char  (mix_iochannel_t *ioc, 
+				  const mix_word_t *w, size_t s)
+{
+  guint k, j;
+  
+  g_return_val_if_fail  (ioc != NULL, FALSE);
+  g_return_val_if_fail (w != NULL, FALSE);
+  
+  for (k = 0; k < s; k++)
+    for (j = 1; j < 6; j++)
+      {
+	mix_char_t ch = mix_word_get_byte (w[k], j);
+	guchar value = mix_char_to_ascii (ch);
+	if (!write_data_ (ioc, &value, 1)) return FALSE;
+      }
+  return TRUE;
+}
+
+gboolean
+mix_io_read_word_array_as_char (mix_iochannel_t *ioc,
+				mix_word_t *w, size_t s)
+{
+  guint k, j;
+  
+  g_return_val_if_fail (ioc != NULL, FALSE);
+  g_return_val_if_fail (w != NULL, FALSE);
+
+  for (k = 0; k < s; k++)
+    for (j = 1; j < 6; j++)
+      {
+	guchar value;
+	if (!read_data_ (ioc, &value, 1)) return FALSE;
+	mix_word_set_byte (&w[k], j, mix_ascii_to_char (value));
+      }
+  return TRUE;
+}
diff --git a/mixlib/mix_io.h b/mixlib/mix_io.h
new file mode 100644
index 0000000..f153398
--- /dev/null
+++ b/mixlib/mix_io.h
@@ -0,0 +1,123 @@
+/* -*-c-*- ------------------ mix_io.h :
+ * Declarations for mix_iochannel_t and mix_file_t
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIX_IOCHANNEL_H
+#define MIX_IOCHANNEL_H
+
+#include <stdio.h>
+#include "mix_types.h"
+
+/* mix_iochannel_t: an object for input/output of mix types */
+typedef struct mix_iochannel_t mix_iochannel_t;
+
+/* Cast to mix_iochannel_t */
+#define MIX_IOCHANNEL(file)  (mix_iochannel_t *)(file)
+
+/* I/O channels can be created in different modes: */
+typedef enum { 
+  mix_io_READ,			/* read existing file */
+  mix_io_WRITE,			/* write new file */
+  mix_io_RDWRT,			/* read/write existing from beginning */
+  mix_io_APPEND,		/* append to existing or new file */
+  mix_io_RAPPEND		/* read from beginning, append to end */
+} mix_fmode_t;
+
+/* Create from a file handle */
+extern mix_iochannel_t *
+mix_io_new (FILE *file);
+
+/* Delete */
+extern void
+mix_io_delete(mix_iochannel_t *ch);
+
+/* Convert to a FILE * */
+extern FILE *
+mix_io_to_FILE (mix_iochannel_t *ioc);
+
+/* Read/write from/to an iochannel */
+extern gboolean
+mix_io_eof(mix_iochannel_t *ioc);
+
+extern gboolean
+mix_io_is_ready(mix_iochannel_t *ioc);
+
+extern gboolean
+mix_io_write_byte(mix_iochannel_t *ioc, mix_byte_t b);
+
+extern gboolean
+mix_io_write_byte_array(mix_iochannel_t *ioc, const mix_byte_t *b,
+			size_t s);
+
+
+extern mix_byte_t
+mix_io_read_byte(mix_iochannel_t *ioc);
+
+extern gboolean
+mix_io_read_byte_array(mix_iochannel_t *ioc, mix_byte_t *b, size_t s);
+
+
+extern gboolean
+mix_io_write_word(mix_iochannel_t *ioc, mix_word_t w);
+
+
+extern gboolean
+mix_io_write_word_array(mix_iochannel_t *ioc, const mix_word_t *w,
+			size_t s);
+
+extern mix_word_t
+mix_io_read_word(mix_iochannel_t *ioc);
+
+extern gboolean
+mix_io_read_word_array(mix_iochannel_t *ioc, mix_word_t *w, size_t s);
+
+extern gboolean
+mix_io_write_short(mix_iochannel_t *ioc, mix_short_t w);
+
+
+extern gboolean
+mix_io_write_short_array(mix_iochannel_t *ioc, const mix_short_t *w,
+			size_t s);
+
+extern mix_short_t
+mix_io_read_short(mix_iochannel_t *ioc);
+
+extern gboolean
+mix_io_read_short_array(mix_iochannel_t *ioc, mix_short_t *w, size_t s);
+
+
+extern gboolean
+mix_io_write_char(mix_iochannel_t *ioc, mix_char_t c);
+
+extern mix_char_t
+mix_io_read_char(mix_iochannel_t *ioc);
+
+extern gboolean
+mix_io_write_word_array_as_char (mix_iochannel_t *ioc, 
+				 const mix_word_t *w, size_t s);
+
+extern gboolean
+mix_io_read_word_array_as_char (mix_iochannel_t *ioc,
+				mix_word_t *w, size_t s);
+
+
+#endif /* MIX_IOCHANNEL_H */
+
diff --git a/mixlib/mix_parser.c b/mixlib/mix_parser.c
new file mode 100644
index 0000000..74317ac
--- /dev/null
+++ b/mixlib/mix_parser.c
@@ -0,0 +1,519 @@
+/* -*-c-*- -------------- mix_parser.c :
+ * Implementation of the functions declared in mix_parser.h and 
+ * xmix_parser.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+#include "mix.h"
+#include "mix_code_file.h"
+#include "xmix_parser.h"
+
+/* The flex-generated scanner, according to file mix_parser.l */
+extern mix_parser_err_t
+mix_flex_scan (mix_parser_t *parser);
+
+/*------------ mixparser.h functions -------------------------------------*/
+
+/* error messages */
+static const gchar * const ERR_MESSAGE_[] = {
+  N_("successful compilation"),
+  N_("file not yet compiled"),
+  N_("internal error"),
+  N_("unable to open MIX source file"),
+  N_("unable to open MIX output file"),
+  N_("unexpected end of file"),
+  N_("invalid location field"),
+  N_("duplicated symbol"),
+  N_("symbol too long"),
+  N_("missing operator field"),
+  N_("unexpected location symbol"),
+  N_("invalid address field"),
+  N_("invalid index field"),
+  N_("invalid f-specification"),
+  N_("invalid operation field"),
+  N_("invalid expression"),
+  N_("undefined symbol"),
+  N_("mismatched parenthesis"),
+  N_("unexpected f-specfication"),
+  N_("missing symbol name"),
+  N_("symbol is an instruction name"),
+  N_("failed write access to code file"),
+  N_("operand of ALF pseudo instruction has less than 5 chars"),
+  N_("operand of ALF pseudo instruction has more than 5 chars")
+};
+
+static const guint NO_OF_MESSAGES_ = sizeof(ERR_MESSAGE_)/sizeof (gchar*);
+
+const gchar *
+mix_parser_err_string (mix_parser_err_t error)
+{
+  return (error < NO_OF_MESSAGES_) ? _(ERR_MESSAGE_[error]) : NULL;
+}
+
+guint 
+mix_parser_err_count (const mix_parser_t *parser)
+{
+  return (parser) ? parser->err_count : 0;
+}
+
+guint 
+mix_parser_warning_count (const mix_parser_t *parser)
+{
+  return (parser) ? parser->warn_count : 0;
+}
+
+const gchar *
+mix_parser_src_file_base_name (const mix_parser_t *parser)
+{
+  return (parser) ? mix_file_base_name (parser->in_file) : NULL;
+}
+
+const gchar *
+mix_parser_src_file_extension (const mix_parser_t *parser)
+{
+  return (parser) ? mix_file_extension (parser->in_file) : NULL;
+}
+
+
+/* Create/destroy a mix_parser */
+/* compare function for the table of ins */
+static gint
+compare_shorts_ (gconstpointer s1, gconstpointer s2)
+{
+  mix_short_t a = (mix_short_t)GPOINTER_TO_UINT(s1);
+  mix_short_t b = (mix_short_t)GPOINTER_TO_UINT (s2);
+  if ( mix_short_sign (a) == mix_short_sign (b) )
+    return mix_short_magnitude (a) - mix_short_magnitude (b);
+  else if ( mix_short_magnitude (a) == 0 && mix_short_magnitude (b) == 0 )
+    return 0;
+  else if ( mix_short_is_positive (a) ) 
+    return 1;
+  return -1;
+}
+
+mix_parser_t *
+mix_parser_new (const gchar *in_file)
+{
+  mix_parser_t *result;
+  mix_file_t *f = mix_file_new_with_def_ext (in_file, mix_io_READ, 
+					     MIX_SRC_DEFEXT);
+  
+  if ( f == NULL ) return NULL;
+  result = g_new (mix_parser_t, 1);
+  if ( result == NULL ) 
+    {
+      g_warning (_("No system resources"));
+      mix_file_delete (f);
+      return NULL;
+    }
+  result->symbol_table = mix_symbol_table_new ();
+  result->ls_table = mix_symbol_table_new ();
+  result->cur_ls = 0;
+  result->future_refs = g_hash_table_new (g_str_hash, g_str_equal);
+  result->ins_table = g_tree_new (compare_shorts_);
+  if ( result->symbol_table == NULL || result->future_refs == NULL
+       || result->ins_table == NULL || result->ls_table == NULL )
+    {
+      mix_symbol_table_delete (result->symbol_table);
+      mix_symbol_table_delete (result->ls_table);
+      g_hash_table_destroy (result->future_refs);
+      g_tree_destroy (result->ins_table);
+      mix_file_delete (f);
+      g_free (result);
+      g_warning (_("No system resources"));
+      return NULL;
+    }
+  result->in_file = f;
+  result->loc_count = MIX_SHORT_ZERO;
+  result->status = MIX_PERR_NOCOMP;
+  result->err_line = 0;
+  result->err_count = 0;
+  result->warn_count = 0;
+  return result;
+}
+
+static void
+delete_list_vals_ (gpointer key, gpointer value, gpointer data)
+{
+  g_free (key);
+  g_slist_free ((GSList*)value);
+}
+
+static int
+delete_tree_vals_ (gpointer key, gpointer value, gpointer data)
+{
+  g_free (value);
+  return FALSE;
+}
+
+void
+mix_parser_delete (mix_parser_t *parser)
+{
+  g_return_if_fail (parser != NULL);
+  /* clear the GSList values of future_refs and its keys */
+  g_hash_table_foreach (parser->future_refs, delete_list_vals_, NULL);
+  /* clear the ins_node_'s of the ins tree */
+  g_tree_traverse (parser->ins_table, delete_tree_vals_, G_IN_ORDER, NULL);
+  /* destroy the tree and hash tables */
+  g_tree_destroy (parser->ins_table);
+  mix_symbol_table_delete (parser->symbol_table);
+  mix_symbol_table_delete (parser->ls_table);
+  g_hash_table_destroy (parser->future_refs);
+  mix_file_delete (parser->in_file);
+  g_free (parser);
+}
+
+/* Compile a mix source file */
+static gboolean
+undef_warning_ (gpointer symbol, gpointer value, gpointer data)
+{
+  mix_parser_log_error ((mix_parser_t *)data, MIX_PERR_UNDEF_SYM, 1,
+			(const gchar *)symbol, TRUE);
+  /* move the symbol to the symbol table */
+  mix_symbol_table_insert_static (((mix_parser_t *)data)->symbol_table, symbol, 
+				  MIX_WORD_ZERO);
+  return TRUE;
+}
+
+static void
+update_future_refs_ (mix_parser_t *parser, const gchar *name)
+{
+  GSList *list = NULL;
+  gpointer key;
+  
+  g_assert (parser != NULL && name != NULL);
+  
+  if ( g_hash_table_lookup_extended (parser->future_refs, name, &key, 
+				     (gpointer *)&list) )
+    {
+      GSList *tmp = list;
+      ins_node_ *node;
+      while ( tmp != NULL )
+	{
+	  node = 
+	    (ins_node_ *)g_tree_lookup (parser->ins_table,tmp->data);
+	  g_assert (node);
+	  mix_word_set_address (node->ins, parser->loc_count);
+	  g_tree_insert (parser->ins_table, tmp->data, (gpointer)node);
+	  tmp = g_slist_next (tmp);
+	}
+      g_hash_table_remove (parser->future_refs, name);
+      g_free (key);
+      g_slist_free (list);
+    }
+}
+
+static void
+update_ls_ (gpointer symbol, gpointer value, gpointer parser)
+{ /* add an instruction on current location and update refs to it */
+  mix_ins_t ins;
+  mix_word_t w = (mix_word_t) GPOINTER_TO_UINT (value);
+  mix_parser_t *par = (mix_parser_t *) parser;
+  
+  mix_word_to_ins_uncheck (w, ins);
+  mix_parser_add_ins (par, &ins, 0);
+  update_future_refs_ (par, (const gchar *)symbol);
+  par->loc_count++;
+}
+
+mix_parser_err_t
+mix_parser_compile (mix_parser_t *parser)
+{
+  g_return_val_if_fail (parser != NULL, MIX_PERR_INTERNAL);
+  g_return_val_if_fail (parser->in_file != NULL, MIX_PERR_NOIN);
+  g_return_val_if_fail (parser->symbol_table != NULL, MIX_PERR_INTERNAL);
+  g_return_val_if_fail (parser->future_refs != NULL, MIX_PERR_INTERNAL);
+  g_return_val_if_fail (parser->ins_table != NULL, MIX_PERR_INTERNAL);
+  
+  parser->status = mix_flex_scan (parser);
+  if ( parser->status == MIX_PERR_OK )
+    {
+      mix_symbol_table_foreach (parser->ls_table, update_ls_, 
+				(gpointer)parser);
+      g_hash_table_foreach_remove (parser->future_refs, 
+				   undef_warning_, (gpointer)parser);
+    }
+  
+  return parser->status;
+}
+
+/* Write a compiled source to a code file */
+struct write_code_context_
+{
+  mix_code_file_t *file;
+  mix_parser_t *parser;
+};
+
+static gint
+write_code_ (gpointer address, gpointer ins_node, gpointer context)
+{
+  mix_ins_desc_t desc;
+  struct write_code_context_ *cntx = (struct write_code_context_ *)context;
+  desc.ins = ((ins_node_ *)ins_node)->ins;
+  desc.lineno = ((ins_node_ *)ins_node)->lineno;
+  desc.address = (mix_address_t)GPOINTER_TO_UINT (address);
+  if ( mix_code_file_write_ins (cntx->file, &desc) )
+    return FALSE;
+  else 
+    {
+      cntx->parser->status = MIX_PERR_NOWRITE;
+      return TRUE;
+    }
+}
+
+mix_parser_err_t
+mix_parser_write_code (mix_parser_t *parser, const gchar *code_file, 
+		       gboolean debug)
+{
+  struct write_code_context_ context;
+  const gchar *cfname = (code_file) ?
+    code_file : mix_file_base_name (parser->in_file);
+  gchar *dir;
+  gchar *source_path;
+    
+  g_return_val_if_fail (parser != NULL, MIX_PERR_INTERNAL);
+  if  (parser->status != MIX_PERR_OK ) return parser->status;
+  context.parser = parser;
+  dir = g_get_current_dir ();
+  source_path = g_strconcat (dir, G_DIR_SEPARATOR_S,
+			     mix_file_base_name (parser->in_file), NULL);
+  context.file = mix_code_file_new_write (cfname, parser->start, source_path,
+					  debug, parser->symbol_table);
+  g_free (dir);
+  g_free (source_path);
+  if (context.file == NULL) return MIX_PERR_NOOUT;
+  g_tree_traverse (parser->ins_table, write_code_, 
+		   G_IN_ORDER, (gpointer)&context);
+  mix_code_file_delete (context.file);
+  return parser->status;
+}
+
+/* Produce a listing file summarising the compilation */
+static gint
+write_listing_ (gpointer address, gpointer ins, gpointer context)
+{
+  guint k;
+  FILE *file = (FILE *)context;
+  ins_node_ *ins_node = (ins_node_ *)ins;
+  mix_ins_t instruct;
+  gchar *instext = NULL;
+
+  mix_ins_id_t id = mix_word_to_ins (ins_node->ins, &instruct);
+  if (id != mix_INVALID_INS)
+    instext = mix_ins_to_string (&instruct);
+  fprintf (file, "%d\t%s ", GPOINTER_TO_INT (address),
+	   mix_word_is_negative (ins_node->ins)? "-":"+");
+  for ( k = 1; k < 6; ++k )
+    fprintf (file, "%02d ", mix_word_get_byte (ins_node->ins, k));
+  fprintf (file, _("\t%s\t(line %d)\n"), instext? instext:"--DATA--",
+	   ins_node->lineno);
+  if (instext) g_free (instext);
+  return FALSE;
+}
+
+mix_parser_err_t
+mix_parser_write_listing (mix_parser_t *parser, const gchar *list_file)
+{
+  FILE *file;
+  mix_file_t *mfile;
+  const gchar *name;
+  
+  g_return_val_if_fail (parser != NULL, MIX_PERR_INTERNAL);
+  if (parser->status != MIX_PERR_OK ) return parser->status;
+  name = (list_file) ? list_file : mix_file_base_name (parser->in_file);
+  mfile =  mix_file_new_with_def_ext (name, mix_io_WRITE, MIX_LIST_DEFEXT);
+  if ( mfile == NULL ) return MIX_PERR_NOOUT;
+  file = mix_file_to_FILE (mfile);
+  fprintf (file, _("*** %s%s: compilation summary ***\n\n"), 
+	   mix_file_base_name (parser->in_file), 
+	   mix_file_extension (parser->in_file));
+  fputs ( _("*** Address / Compiled word / Symbolic rep / Source file line\n"),
+	  file);
+  g_tree_traverse (parser->ins_table, write_listing_, 
+		   G_IN_ORDER, (gpointer)file);
+  fprintf (file, _("\n*** Start address: %d\n"), 
+	   mix_short_magnitude (parser->start));
+  fprintf (file, _("\n*** Symbol table\n"));
+  mix_symbol_table_print (parser->symbol_table, MIX_SYM_ROWS, file);
+  fprintf (file, _("\n*** End of summary ***\n"));
+  mix_file_delete (mfile);
+  return parser->status;
+}
+
+/* load a virtual machine's memory with the contents of a compiled file */
+static gint
+load_vm_ (gpointer address, gpointer ins, gpointer vm)
+{
+  mix_vm_set_addr_contents ((mix_vm_t*)vm,
+			    (mix_address_t)GPOINTER_TO_UINT (address), 
+			    ((ins_node_ *)ins)->ins);
+  return FALSE;
+}
+
+mix_parser_err_t
+mix_parser_load_vm (const mix_parser_t *parser, mix_vm_t *vm)
+{
+  g_return_val_if_fail (parser != NULL, MIX_PERR_INTERNAL);
+  g_return_val_if_fail (vm != NULL, MIX_PERR_INTERNAL);
+  g_return_val_if_fail (parser->status == MIX_PERR_OK, parser->status);
+  mix_vm_reset (vm);
+  g_tree_traverse (parser->ins_table, load_vm_, G_IN_ORDER, (gpointer)vm);
+  mix_vm_set_start_addr (vm, parser->start);
+  return parser->status;
+}
+
+
+
+/*------------ xmiparser.h functions -------------------------------------*/
+/* functions to manipulate mix_parser_t during compilation */
+
+
+/* symbol table */
+/* Define a new symbol with value equal to the current loc_count
+ * and update future refs to this symbol
+ */
+mix_parser_err_t
+mix_parser_define_symbol_here (mix_parser_t *parser, const gchar *name)
+{
+  mix_word_t value = mix_short_to_word_fast (parser->loc_count);
+  
+  g_assert (parser != NULL && name != NULL);  
+  
+  switch (mix_symbol_table_add (parser->symbol_table, name, value))
+    {
+    case MIX_SYM_OK: 
+      if ( parser->status == MIX_PERR_NOCOMP ) 
+	update_future_refs_ (parser, name);
+      return MIX_PERR_OK;
+    case MIX_SYM_LONG: return MIX_PERR_LONG_SYMBOL;
+    case MIX_SYM_DUP: return MIX_PERR_DUP_SYMBOL;
+    default: return MIX_PERR_INTERNAL;
+    }
+}
+
+/* Obtain the value of a symbol */
+void
+mix_parser_set_future_ref (mix_parser_t *parser, const gchar *name)
+{
+  const gchar *nname = name;
+  GSList *list;
+
+  g_assert (parser != NULL && name != NULL);
+
+  if ( parser->status == MIX_PERR_NOCOMP )
+    {
+      list =  g_hash_table_lookup (parser->future_refs, name);
+      if ( list == NULL ) nname = g_strdup (name);
+      list = g_slist_prepend (list, (gpointer)((guint)parser->loc_count));
+      g_hash_table_insert (parser->future_refs, (gpointer)nname, list);
+    }
+}
+
+/* Redefine the value of a local symbol as the current loc_count */
+void
+mix_parser_manage_local_symbol (mix_parser_t *parser, const gchar *name)
+{
+  gchar ref[3];
+  ref[2] = 0;
+    
+  g_assert (parser != NULL && name != NULL);
+  g_assert (strlen(name) == 2);
+  
+  switch (name[1])
+    {
+    case 'f': case 'F':
+      mix_parser_set_future_ref (parser, name);
+      break;
+    case 'h': case 'H':
+      ref[0] = name[0];
+      ref[1] = 'F';
+      if ( parser->status == MIX_PERR_NOCOMP ) 
+	update_future_refs_ (parser, ref);
+      ref[1] = 'B';
+      mix_symbol_table_insert (parser->symbol_table, ref, 
+			       mix_short_to_word_fast (parser->loc_count));
+      break;
+    default:
+      return;
+    }
+}
+
+/* Literal strings symbols */
+void
+mix_parser_define_ls (mix_parser_t *parser, mix_word_t value)
+{
+  gchar *name = g_strdup_printf ("%05d", parser->cur_ls++);
+  mix_symbol_table_add (parser->ls_table, name, value);
+  mix_parser_set_future_ref (parser, name);
+  g_free (name);
+}
+
+/* Compilation */
+void
+mix_parser_add_ins (mix_parser_t *parser, const mix_ins_t *new_ins, 
+		    guint lineno)
+{
+  g_assert (parser != NULL && new_ins != NULL);
+  mix_parser_add_raw (parser, mix_ins_to_word_uncheck (*new_ins), lineno);
+}
+
+void
+mix_parser_add_raw (mix_parser_t *parser, mix_word_t word, guint lineno)
+{
+  g_assert (parser != NULL);
+  if ( parser->status == MIX_PERR_NOCOMP || parser->status == MIX_PERR_OK )
+    {
+      ins_node_ *node = g_new (ins_node_, 1);
+      if ( node == NULL ) {
+	g_warning (_("Unable to allocate memory"));
+	return;
+      }
+      node->ins = word;
+      node->lineno = lineno;
+      g_tree_insert (parser->ins_table, (gpointer)((guint)parser->loc_count),
+		     (gpointer)node);
+    }
+}
+
+/* Error handling */
+void 
+mix_parser_log_error (mix_parser_t *parser, mix_parser_err_t error,
+		      gint lineno, const gchar *comment, gboolean warn)
+{
+  g_assert (parser != NULL);
+  if ( warn )
+    parser->warn_count += 1;
+  else
+    {
+      parser->err_count += 1;
+      parser->err_line = lineno;
+      parser->status = error;
+    }
+    
+  fprintf (stderr, "%s%s:%d: %s: %s",
+	   mix_file_base_name (parser->in_file), 
+	   mix_file_extension (parser->in_file),
+	   lineno, warn ? _("warning"):_("error"), _(ERR_MESSAGE_[error]));
+
+  if (comment != NULL)
+    fprintf (stderr, ": %s\n", comment);
+  else
+    fputs ("\n", stderr);
+}
+
diff --git a/mixlib/mix_parser.h b/mixlib/mix_parser.h
new file mode 100644
index 0000000..cd1a047
--- /dev/null
+++ b/mixlib/mix_parser.h
@@ -0,0 +1,110 @@
+/* -*-c-*- ---------------- mix_parser.h :
+ * Declarations for mix_parser_t, which compiles a source file into
+ * a mix code file.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIX_PARSER_H
+#define MIX_PARSER_H
+
+#include <glib.h>
+#include "mix_vm.h"
+
+/* The parser type */
+typedef struct mix_parser_t mix_parser_t;
+
+/* Create/destroy a mix_parser */
+extern mix_parser_t *
+mix_parser_new(const gchar *in_file);
+
+extern void
+mix_parser_delete(mix_parser_t *parser);
+
+/* Access source file name */
+extern const gchar *
+mix_parser_src_file_base_name(const mix_parser_t *parser);
+
+extern const gchar *
+mix_parser_src_file_extension(const mix_parser_t *parser);
+
+/* Compile a mix source file */
+/* compilation errors */
+typedef enum { 
+  MIX_PERR_OK,		/* no error */
+  MIX_PERR_NOCOMP,	/* file not yet compiled */
+  MIX_PERR_INTERNAL,	/* internal error */
+  MIX_PERR_NOIN,	/* unable to open input file */
+  MIX_PERR_NOOUT,	/* unable to open output file */
+  MIX_PERR_UNEX_EOF,	/* unexpected end of file */
+  MIX_PERR_INV_LOC,	/* invalid loc field */
+  MIX_PERR_DUP_SYMBOL,	/* duplicated symbol */
+  MIX_PERR_LONG_SYMBOL,	/* symbol name too long */
+  MIX_PERR_NOOP,	/* missing op field */
+  MIX_PERR_UNEX_LOC,	/* unexpected location symbol */
+  MIX_PERR_INV_ADDRESS, /* invalid address field */
+  MIX_PERR_INV_IDX,	/* invalid index field */
+  MIX_PERR_INV_FSPEC,	/* invalid fspec */
+  MIX_PERR_INV_OP,	/* invalid operation */
+  MIX_PERR_INV_EXPR,	/* invalid expression */
+  MIX_PERR_UNDEF_SYM,	/* undefined symbol */
+  MIX_PERR_MIS_PAREN,	/* mismatched parenthesis */
+  MIX_PERR_UNEX_FSPEC,	/* unexpected f-spec */
+  MIX_PERR_MIS_SYM,	/* missing symbol name */
+  MIX_PERR_SYM_INS,	/* symbol has the same name as instruction */
+  MIX_PERR_NOWRITE,	/* failed code write */
+  MIX_PERR_SHORT_ALF,	/* short ALF operand */
+  MIX_PERR_LONG_ALF	/* too long ALF operand */
+} mix_parser_err_t;
+
+extern const gchar *
+mix_parser_err_string(mix_parser_err_t error);
+
+extern mix_parser_err_t
+mix_parser_compile(mix_parser_t *parser);
+
+extern guint 
+mix_parser_warning_count(const mix_parser_t *parser);
+
+extern guint 
+mix_parser_err_count(const mix_parser_t *parser);
+
+/* Write the compilation result to a code file with the given name.
+   code_file is completed, if required, with the requisite extension;
+   if code_file == NULL [source_file_name].[extension] is used.
+   If debug == TRUE, debug information is written.
+*/
+extern mix_parser_err_t
+mix_parser_write_code(mix_parser_t *parser, const gchar *code_file,
+		      gboolean debug);
+
+/* Write a "canonical" listing of a compiled source, i.e. a source
+   file with all symbols substituted by their actual values after
+   compilation.
+*/
+extern mix_parser_err_t
+mix_parser_write_listing(mix_parser_t *parser, const gchar *list_file);
+
+/* load a virtual machine's memory with the contents of a compiled file */
+extern mix_parser_err_t
+mix_parser_load_vm(const mix_parser_t *parser, mix_vm_t *vm);
+
+
+#endif /* MIX_PARSER_H */
+
diff --git a/mixlib/mix_scanner.l b/mixlib/mix_scanner.l
new file mode 100644
index 0000000..f740d10
--- /dev/null
+++ b/mixlib/mix_scanner.l
@@ -0,0 +1,497 @@
+/* -*-c-*- ------------------ mix_scanner.l :
+ * Lexical scanner used by mix_parser_t
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+%{
+#include "mix.h"
+#include "xmix_parser.h"
+
+#define YY_DECL mix_parser_err_t mix_flex_scan (mix_parser_t *parser)
+
+#define RESET()					\
+  do {						\
+    mix_ins_fill_from_id (ins, mix_NOP);	\
+    ins.address = 0;				\
+    ins.index = 0;				\
+    nof = FALSE;				\
+    lsf = FALSE;				\
+    if (symbol != NULL )			\
+     {						\
+       g_free (symbol);				\
+       symbol = NULL;				\
+     }						\
+  } while (FALSE)
+
+#define NEXT()				\
+  do {						\
+    parser->loc_count++;			\
+    RESET ();					\
+    ++lineno;					\
+    BEGIN (INITIAL);				\
+  } while (FALSE)
+
+#define ADD_INS()				\
+  do {						\
+    mix_parser_add_ins (parser, &ins, lineno);	\
+    NEXT ();	               			\
+  } while (FALSE)
+
+#define ADD_RAW(value)				\
+  do {						\
+    mix_parser_add_raw (parser, value, lineno);	\
+    NEXT ();	               			\
+  } while (FALSE)
+
+
+#define ENTER_EVAL()				\
+  do {						\
+    expr_val = MIX_WORD_ZERO;			\
+    yyless (0);					\
+    yy_push_state (EVAL);			\
+  } while (FALSE)
+
+#define ENTER_WEVAL()				\
+  do {						\
+    wexpr_val = MIX_WORD_ZERO;			\
+    wexpr_val_tmp = MIX_WORD_ZERO;		\
+    is_fp = FALSE;                              \
+    yyless (0);					\
+    yy_push_state (WEVAL);			\
+  } while (FALSE)
+
+#define RETURN_ERROR(error, comment)				\
+  do {								\
+    char c;							\
+    mix_parser_log_error (parser,error,lineno,comment,FALSE);	\
+    while ( (c = input ()) != '\n' && c != EOF ) ;		\
+    if ( c == EOF ) return error; else ++lineno;		\
+    RESET ();							\
+    BEGIN (INITIAL);						\
+  } while (FALSE)
+
+ 
+static mix_word_t
+  eval_binop_ (const gchar *op, mix_word_t x, mix_word_t y);
+ 
+static void
+  unput_word_ (mix_word_t word);
+ 
+%}
+
+%option nomain
+%option caseless
+%option pointer
+%option stack
+%option noyywrap
+%option noyy_top_state
+%option noreject
+%option outfile="lex.yy.c"
+
+%s  LOC
+%s  OP
+%s  ADDRESS
+%s  INDEX
+%s  FSPEC
+%s  EVAL
+%s  WEVAL
+%s  ORIG
+%s  CON
+%s  EQU
+%s  END
+
+ws	[ \t]+
+digit	[0-9]
+letter	[A-Z]
+number	[+-]?{digit}+
+mixchar [0-9A-Z .,'')(+*/=$<>@;:\-]
+locsymbol   {digit}H
+flocsymbol  {digit}F
+blocsymbol  {digit}B
+symbol	{digit}*{letter}+[A-Z0-9]*
+binop	"+"|"-"|"*"|"/"|"//"|":"
+atexpr	{digit}+|{symbol}|\*
+expr	[+-]?{atexpr}({binop}{1}{atexpr})*
+fpart   \({expr}\)
+wexpr   {expr}({fpart})?(,{expr}({fpart})?)*
+  
+
+%%
+
+%{
+
+  mix_ins_t ins;
+  gboolean nof = FALSE, is_fp = FALSE, end = FALSE, lsf = FALSE;
+  mix_word_t expr_val = MIX_WORD_ZERO, wexpr_val = MIX_WORD_ZERO,
+  wexpr_val_tmp = MIX_WORD_ZERO;
+  gchar *symbol = NULL;
+  guint lineno = 1;
+  mix_ins_fill_from_id (ins, mix_NOP);		
+  ins.address = 0;				
+  ins.index = 0;				
+  parser->err_line = 0;
+  yyin = mix_file_to_FILE (parser->in_file);
+  
+%}
+  
+
+<*><<EOF>> {
+  mix_parser_log_error (parser, MIX_PERR_UNEX_EOF, lineno, NULL, FALSE);
+  return MIX_PERR_UNEX_EOF;
+}
+
+<INITIAL>{
+  ^\*.*	/* eat comments */
+  .	{
+    if ( end ) return parser->status;
+    yyless (0);
+    BEGIN (LOC);
+  }
+  \n { 
+    ++lineno;
+    if ( end ) return parser->status; 
+  }
+}			
+
+<LOC>{
+  {ws}+	BEGIN (OP); /* LOC field is empty */
+  {locsymbol} { /* manage local symbol */
+    mix_parser_manage_local_symbol (parser,yytext);
+    BEGIN (OP);
+  }
+  {flocsymbol}|{blocsymbol} RETURN_ERROR (MIX_PERR_UNEX_LOC, yytext);
+  {symbol}/{ws}+EQU { /* store symbol name for future definition */
+    symbol = g_strdup (yytext);
+    if ( symbol == NULL ) {
+      mix_parser_log_error (parser, MIX_PERR_INTERNAL, lineno, NULL, FALSE);
+      return MIX_PERR_INTERNAL;
+    }
+    BEGIN (OP);
+  }
+  {symbol} { /* define a new symbol */
+    mix_parser_err_t err;
+    if ( mix_get_id_from_string (yytext) != mix_INVALID_INS )
+      mix_parser_log_error (parser, MIX_PERR_SYM_INS, lineno, yytext, TRUE);
+    if ( (err = mix_parser_define_symbol_here (parser,yytext)) != MIX_PERR_OK )
+      mix_parser_log_error (parser, err, lineno, yytext, FALSE);
+    BEGIN (OP);
+  }
+  .	RETURN_ERROR (MIX_PERR_INV_LOC, yytext);
+  \n 	++lineno; /* empty line */
+}
+
+<OP>{
+  {ws} /* eat leading whitespace */
+  \n    RETURN_ERROR (MIX_PERR_NOOP, NULL);
+  ORIG{ws}+  BEGIN (ORIG);
+  CON{ws}+   BEGIN (CON);
+  EQU{ws}+   BEGIN (EQU);
+  END{ws}+   BEGIN (END);
+  ALF{ws}+\"{mixchar}{5,}\"{ws}+.*\n |
+  ALF{ws}+\"{mixchar}{5,}\"{ws}*\n {
+    mix_byte_t bytes[5];
+    mix_word_t value;
+    guint k, j = 4;
+
+    while ( yytext[j++] != '\"' ) ;
+    for ( k = j; k < 5+j && yytext[k] != '\"'; ++k )
+      bytes[k-j] = mix_ascii_to_char (yytext[k]);
+    if ( k-j < 5 )
+      mix_parser_log_error (parser, MIX_PERR_SHORT_ALF, lineno, NULL, TRUE);
+    else if ( yytext[k] != '\"' )
+      mix_parser_log_error (parser, MIX_PERR_LONG_ALF, lineno, NULL, TRUE);
+
+    value = mix_bytes_to_word (bytes, 5);
+    
+    ADD_RAW (value);
+   }
+  [A-Z0-9]+{ws}*/\n |    
+  [A-Z0-9]+{ws}+ {
+    mix_ins_id_t id = mix_get_id_from_string (g_strchomp (yytext));
+    if ( id == mix_INVALID_INS )
+      mix_parser_log_error (parser, MIX_PERR_INV_OP, lineno, yytext, FALSE);
+    else {
+      mix_ins_fill_from_id (ins, id);
+      nof = mix_ins_id_is_extended (id);
+    }
+    BEGIN (ADDRESS);
+  }
+  {expr} RETURN_ERROR (MIX_PERR_INV_OP, yytext);
+  .  RETURN_ERROR (MIX_PERR_INV_OP, yytext);		
+}
+
+
+<ORIG>{
+  {number}{ws}*\n   |
+  {number}{ws}+.*\n {
+    mix_word_t value = mix_word_new (atol (yytext));
+    parser->loc_count = mix_word_to_short_fast (value);
+    ++lineno;
+    BEGIN (INITIAL);
+  }
+}
+
+<CON>{
+  {number}{ws}*\n |
+  {number}{ws}+.*\n  {
+    mix_word_t value = mix_word_new (atol (yytext));
+    mix_word_to_ins_uncheck (value, ins);
+    ADD_INS ();
+  }
+}
+
+<EQU>{
+  {number}{ws}*\n   |
+  {number}{ws}+.*\n {
+    mix_word_t value;
+    gint def;
+    if ( symbol == NULL ) RETURN_ERROR (MIX_PERR_MIS_SYM, NULL);
+    value = mix_word_new (atol (yytext));
+    def = mix_symbol_table_add (parser->symbol_table, symbol, value);
+    if ( def == MIX_SYM_DUP )  RETURN_ERROR (MIX_PERR_DUP_SYMBOL, symbol);
+    if ( def == MIX_SYM_LONG )  RETURN_ERROR (MIX_PERR_LONG_SYMBOL, symbol);
+    ++lineno;
+    BEGIN (INITIAL);
+  }
+}
+
+<END>{
+  {number}{ws}*\n   |
+  {number}{ws}+.*\n {
+    parser->start = mix_short_new (atol (yytext));
+    end = TRUE;
+    if ( parser->status == MIX_PERR_NOCOMP ) parser->status = MIX_PERR_OK;
+    return parser->status;
+  }
+}
+
+<ORIG,CON,EQU,END>{
+  {wexpr} ENTER_WEVAL ();
+  . RETURN_ERROR (MIX_PERR_INV_OP, yytext);
+}
+
+
+<ADDRESS,INDEX,FSPEC>{locsymbol}  RETURN_ERROR (MIX_PERR_UNEX_LOC, yytext);
+
+<ADDRESS>{
+  =/[+-]?{number}=  lsf = TRUE;
+  =/{expr}=     lsf = TRUE;
+  [+-]?{number}={ws}*\n   |
+  [+-]?{number}={ws}+.*\n {
+    if (!lsf) RETURN_ERROR (MIX_PERR_INV_ADDRESS, yytext);
+    mix_parser_define_ls (parser, mix_word_new (atol (yytext)));
+    ADD_INS ();
+  }
+  [+-]?{number}{ws}+.*\n |
+  [+-]?{number}[(,\n] {
+    ins.address = mix_short_new (atol (yytext));
+    switch ( yytext[yyleng-1] ) {
+    case '(' : BEGIN (FSPEC); break; 
+    case ',' : BEGIN (INDEX); break;
+    case '\n' : ADD_INS (); break;
+    default: g_assert_not_reached ();
+    }
+  }
+  ([+-]?{symbol})/[(,\n\t ] {
+    gboolean neg = (yytext[0] == '-');
+    const gchar *s = (neg || yytext[0] == '+')? yytext+1 : yytext;
+    if ( !mix_symbol_table_is_defined (parser->symbol_table, s) )
+      {
+	mix_parser_set_future_ref (parser, s);
+	unput ('0');
+      }
+    else
+      {
+	mix_word_t v = mix_symbol_table_value (parser->symbol_table, s);
+	if ( neg ) mix_word_reverse_sign (v);
+	unput_word_ (v);
+      }
+  }
+  {expr}/[(,=\n\t ] ENTER_EVAL ();
+  \n    ADD_INS ();
+  .	RETURN_ERROR (MIX_PERR_INV_ADDRESS, yytext);
+}
+	
+
+<INDEX>{
+  {number}[\n(\t ] {
+    int end = yytext[yyleng-1];
+    ins.index = mix_byte_new (atol (yytext));
+    if ( end == '\n' )
+      ADD_INS ();
+    else if ( end == '(' )
+      BEGIN (FSPEC);
+    else
+      { /* eat rest of line (comment) */
+	while ( (end = input()) != '\n' && end != EOF ) ;
+	if ( end == '\n' ) ADD_INS ();
+	else RETURN_ERROR (MIX_PERR_UNEX_EOF, NULL);
+      }
+  }
+  {expr}/[\n(\t ]  ENTER_EVAL ();
+  \n	{
+    mix_parser_log_error (parser, MIX_PERR_INV_IDX, lineno++, NULL, FALSE);
+    RESET (); 
+    BEGIN (INITIAL);
+  }
+  .	RETURN_ERROR (MIX_PERR_INV_IDX, yytext);
+}
+
+<FSPEC>{
+  {number}")"(({ws}+.*\n)|\n) {
+    glong val  = atol (yytext);
+    if ( val < 0 || val > MIX_BYTE_MAX ) 
+      RETURN_ERROR (MIX_PERR_INV_FSPEC, NULL);
+    if ( ins.opcode != mix_opMOVE 
+         && ( ins.opcode < mix_opJBUS || ins.opcode > mix_opJXx )
+         && !mix_fspec_is_valid (mix_byte_new (val)) )
+      RETURN_ERROR (MIX_PERR_INV_FSPEC, NULL);
+    if ( nof ) 
+      mix_parser_log_error (parser, MIX_PERR_INV_FSPEC,
+			    lineno, _("ignored"), TRUE);
+    else
+      {
+	ins.fspec = mix_byte_new (val);
+	ADD_INS ();
+      }
+  }
+  {expr}/")"  {
+    ENTER_EVAL ();
+  }
+  .	RETURN_ERROR (MIX_PERR_INV_FSPEC, yytext);
+}
+
+
+<EVAL>{
+  {binop}{digit}+ {
+    const gchar *s = ( yytext[1] == '/' ) ? yytext+2 : yytext+1;
+    mix_word_t value = mix_word_new (atol (s));
+    expr_val = eval_binop_ (yytext, expr_val, value);
+  }
+  {binop}{symbol} {
+    const gchar *s = ( yytext[1] == '/' ) ? yytext+2 : yytext+1;
+    if ( !mix_symbol_table_is_defined (parser->symbol_table, s) ) {
+      mix_parser_log_error (parser, MIX_PERR_UNDEF_SYM, lineno, s, FALSE);
+      yy_pop_state ();
+    }
+    expr_val = eval_binop_ (yytext, expr_val, 
+			    mix_symbol_table_value (parser->symbol_table, s));
+  }
+  {binop}"*" {
+    expr_val = eval_binop_ (yytext, expr_val, 
+			    mix_short_to_word_fast (parser->loc_count));
+  }
+  "*"         unput_word_ (mix_short_to_word_fast (parser->loc_count));
+  {number}    expr_val = mix_word_new (atol (yytext));
+  {symbol} {
+    if ( !mix_symbol_table_is_defined (parser->symbol_table, yytext) ) {
+      mix_parser_log_error (parser, MIX_PERR_UNDEF_SYM, lineno, yytext, FALSE);
+      yy_pop_state ();
+    }
+    expr_val = mix_symbol_table_value (parser->symbol_table, yytext);
+  }
+  [,)(=\n\t ]   unput (yytext[0]); unput_word_ (expr_val); yy_pop_state ();
+  .   RETURN_ERROR (MIX_PERR_INV_EXPR, yytext);
+}
+
+<WEVAL>{
+  {number}"(" {
+    is_fp = TRUE;
+    wexpr_val_tmp = mix_word_new (atol (yytext));
+  }
+  {number}")"  {
+    glong val  = atol (yytext);
+    if ( !is_fp ) {
+      mix_parser_log_error (parser, MIX_PERR_MIS_PAREN, lineno, NULL, FALSE);
+      yy_pop_state ();
+    }
+    if ( val < 0 || val > MIX_BYTE_MAX 
+         || !mix_fspec_is_valid (mix_byte_new (val)) ) {
+      mix_parser_log_error (parser, MIX_PERR_INV_FSPEC, lineno, NULL, FALSE);
+      yy_pop_state ();
+    }
+    is_fp = FALSE;
+    wexpr_val = mix_word_store_field (mix_byte_new (val), wexpr_val_tmp, 
+				      wexpr_val);
+  }
+  {number} wexpr_val = mix_word_new (atol (yytext));
+  {expr}  ENTER_EVAL ();
+  ,/{expr} /* eat comma if followed by expression */
+  [\n\t ] { /* ok if not inside an f-part */
+    if ( is_fp ) {
+      mix_parser_log_error (parser, MIX_PERR_MIS_PAREN, lineno, NULL, FALSE);
+      yy_pop_state ();
+     }
+    unput (yytext[yyleng-1]);
+    unput_word_ (wexpr_val);
+    yy_pop_state ();
+  }
+  .  RETURN_ERROR (MIX_PERR_INV_EXPR, NULL);
+}
+
+%%
+
+static mix_word_t
+eval_binop_ (const gchar *op, mix_word_t x, mix_word_t y)
+{
+  mix_word_t result = MIX_WORD_ZERO;
+  switch (op[0])
+    {
+    case '+': 
+      result = mix_word_add (x,y); 
+      break;
+    case '-':
+      result = mix_word_sub (x,y);
+      break;
+    case '*':
+      mix_word_mul (x, y, NULL, &result);
+      break;
+    case ':':
+      {
+	mix_word_t a;
+	mix_word_mul (x, 8, NULL, &a);
+	result = mix_word_add (a, y);
+	break;
+      }
+    case '/':
+      if ( strlen (op) > 1 && op[1] == '/' ) {
+	mix_word_div (x,MIX_WORD_ZERO,y, &result, NULL);
+      } else {
+	mix_word_div (MIX_WORD_ZERO, x, y, &result, NULL);
+      }
+      break;
+    default:
+      g_assert_not_reached ();
+    }
+  return result;
+}
+
+
+static void
+unput_word_ (mix_word_t word)					
+{								
+  gchar *value;						
+  gint k;							
+  value = g_strdup_printf ("%s%ld",				
+			   mix_word_is_negative (word)? "-":"+",
+			   mix_word_magnitude (word));		
+  for (k = strlen (value) - 1; k >= 0; --k)			
+    unput (value[k]);						
+  g_free (value);						
+}
diff --git a/mixlib/mix_symbol_table.c b/mixlib/mix_symbol_table.c
new file mode 100644
index 0000000..7f3c4df
--- /dev/null
+++ b/mixlib/mix_symbol_table.c
@@ -0,0 +1,139 @@
+/* -*-c-*- -------------- mix_symbol_table.c :
+ * Implementation of the functions declared in mix_symbol_table.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#include "mix_symbol_table.h"
+
+/* Create an empty table */
+mix_symbol_table_t *
+mix_symbol_table_new(void)
+{
+  return g_hash_table_new(g_str_hash, g_str_equal);
+}
+
+/* Create a table and populate it with the contents of a table stored
+   in -file- using mix_symbol_table_print(table, MIX_SYM_LINE, file)
+*/
+mix_symbol_table_t *
+mix_symbol_table_new_from_file(FILE *file)
+{
+  mix_symbol_table_t *result = mix_symbol_table_new();
+  if ( result != NULL )
+    {
+      gchar sym[MIX_SYM_MAX_LEN + 1];
+      glong val;
+      
+      while ( getc(file) == ',' )
+	{
+	  if ( fscanf(file, "%s =%ld", sym, &val) != EOF )
+	      mix_symbol_table_add(result, sym, mix_word_new(val));
+	}
+    }
+  return result;
+}
+
+/* Delete a table */
+static void
+delete_hash_keys_(gpointer key, gpointer value, gpointer data)
+{
+  g_free(key);
+}
+
+void
+mix_symbol_table_delete(mix_symbol_table_t *table)
+{
+  g_hash_table_foreach(table, delete_hash_keys_, NULL);
+  g_hash_table_destroy(table);
+}
+
+
+/* Add/remove symbols one by one */
+gint
+mix_symbol_table_add(mix_symbol_table_t *table, 
+		     const gchar *sym, mix_word_t value)
+{
+  gpointer key, val;
+  
+  if ( table == NULL || sym == NULL ) return MIX_SYM_FAIL;
+  if ( strlen(sym) > MIX_SYM_MAX_LEN ) return  MIX_SYM_LONG;
+
+  if ( !g_hash_table_lookup_extended(table, sym, &key, &val) )
+    {
+      key = g_strdup(sym);
+      g_hash_table_insert(table, key, (gpointer)value);
+      return MIX_SYM_OK;
+    }
+  else
+    return MIX_SYM_DUP;
+}
+
+/* Add or modify symbol if it exists */
+gint
+mix_symbol_table_insert(mix_symbol_table_t *table, 
+			const gchar *sym, mix_word_t new_value)
+{
+  gpointer key, val;
+  
+  if ( table == NULL || sym == NULL ) return MIX_SYM_FAIL;
+  if ( strlen(sym) > MIX_SYM_MAX_LEN ) return MIX_SYM_LONG;
+
+  if ( !g_hash_table_lookup_extended(table, sym, &key, &val) )
+      key = g_strdup(sym);
+  g_hash_table_insert(table, key, (gpointer)new_value);
+  return MIX_SYM_OK;
+}
+
+
+/* Symbols lookup */
+gboolean
+mix_symbol_table_is_defined(const mix_symbol_table_t *table, const gchar *sym)
+{
+  gpointer key, val;
+  return g_hash_table_lookup_extended((GHashTable *)table, sym, &key, &val);
+}
+
+/* Print table */
+static void
+print_sym_rows_(gpointer symbol, gpointer value, gpointer file)
+{
+  mix_word_t word = (mix_word_t)GPOINTER_TO_UINT(value);
+  fprintf((FILE *)file, "%s:  %s%ld\n", (gchar *)symbol, 
+	  mix_word_is_negative(word)? "-":"", mix_word_magnitude(word));
+}
+
+static void
+print_sym_line_(gpointer symbol, gpointer value, gpointer file)
+{
+  mix_word_t word = (mix_word_t)GPOINTER_TO_UINT(value);
+  fprintf((FILE *)file, ",%s =%s%ld", (gchar *)symbol, 
+	  mix_word_is_negative(word)? "-":"", mix_word_magnitude(word));
+}
+
+void
+mix_symbol_table_print(const mix_symbol_table_t *table, gint mode, FILE *file)
+{
+  GHFunc func = (mode == MIX_SYM_LINE)? print_sym_line_ : print_sym_rows_;
+  if ( table != NULL )
+    g_hash_table_foreach((GHashTable *)table, func, (gpointer)file);
+  if ( mode == MIX_SYM_LINE ) putc(';', file); /* to mark end-of-table */
+}
+
+  
diff --git a/mixlib/mix_symbol_table.h b/mixlib/mix_symbol_table.h
new file mode 100644
index 0000000..d9eaede
--- /dev/null
+++ b/mixlib/mix_symbol_table.h
@@ -0,0 +1,99 @@
+/* -*-c-*- ---------------- mix_symbol_table.h :
+ * Type mix_symbol_table_t and functions to manipulate it.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIX_SYMBOL_TABLE_H
+#define MIX_SYMBOL_TABLE_H
+
+#include <stdio.h>
+#include "mix_types.h"
+
+/* A symbol table shall be implemented as a hash table */
+typedef GHashTable mix_symbol_table_t ;
+
+/* Maximum length of stored symbols */
+#define MIX_SYM_MAX_LEN  10
+
+/* Create an empty table */
+extern mix_symbol_table_t *
+mix_symbol_table_new(void);
+
+/* Create a table and populate it with the contents of a table stored
+   in -file- using mix_symbol_table_print(table, MIX_SYM_LINE, file)
+*/
+extern mix_symbol_table_t *
+mix_symbol_table_new_from_file(FILE *file);
+
+
+/* Delete a table */
+extern void
+mix_symbol_table_delete(mix_symbol_table_t *table);
+
+/* Add/remove symbols one by one */
+/* possible outcomes: */
+enum { 
+  MIX_SYM_FAIL, /* attempt failed */
+  MIX_SYM_OK, 
+  MIX_SYM_DUP,  /* duplicated symbol */
+  MIX_SYM_LONG  /* symbol too long: only MIX_SYM_MAX_LEN chars used */
+};
+
+extern gint
+mix_symbol_table_add(mix_symbol_table_t *table, 
+		     const gchar *sym, mix_word_t value);
+
+#define mix_symbol_table_remove(table, sym) \
+  g_hash_table_remove(table, sym)
+
+
+/* Add or modify symbol if it exists */
+extern gint
+mix_symbol_table_insert(mix_symbol_table_t *table, 
+			const gchar *sym, mix_word_t new_value);
+
+/* Add or modify symbol if it exists, without copiying sym */
+#define mix_symbol_table_insert_static(table,sym,value)\
+	g_hash_table_insert(table,(gpointer)sym,GUINT_TO_POINTER(value))
+
+/* Symbols lookup */
+extern gboolean
+mix_symbol_table_is_defined(const mix_symbol_table_t *table, const gchar *sym);
+
+#define mix_symbol_table_value(table,sym)				    \
+  (mix_word_t)GPOINTER_TO_UINT (g_hash_table_lookup ((GHashTable *)table, \
+                                (gpointer)sym))
+
+/* Traverse the table */
+#define mix_symbol_table_foreach(table,func,data) \
+	g_hash_table_foreach(table,func,data)
+
+/* Print the table */
+enum {
+  MIX_SYM_ROWS, /* each symbol/value in a row */
+  MIX_SYM_LINE  /* {,symbol =value}*; in a single row */
+};
+
+extern void
+mix_symbol_table_print(const mix_symbol_table_t *table, gint mode, FILE *file);
+
+
+#endif /* MIX_SYMBOL_TABLE_H */
+
diff --git a/mixlib/mix_types.c b/mixlib/mix_types.c
new file mode 100644
index 0000000..32b505f
--- /dev/null
+++ b/mixlib/mix_types.c
@@ -0,0 +1,543 @@
+/* -*-c-*- ------------------ mix_types.c :
+ *  Implementation file for mix_types.h declarations.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+#include "mix.h"
+#include <limits.h>
+#include "mix_types.h"
+
+
+/*------------------------ initialisation stuff ------------------------*/
+/* flag telling whether a field spec is valid */
+static gboolean is_bad_field_[MIX_BYTE_MAX + 1];
+/* shift associated with a fspec */  
+static guint shift_[MIX_BYTE_MAX + 1];
+/* mask associated with a fspec */
+static glong mask_[MIX_BYTE_MAX + 1];
+
+/* maps from gchar's to mix_char_t */
+#define NONP_  (guchar)('?')
+static mix_char_t ascii_to_mix_char_[UCHAR_MAX + 1];
+static guchar mix_char_to_ascii_[MIX_CHAR_MAX + 1] = {
+  ' ', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'd', 'J',
+  'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 's', 'p', 'S', 'T',
+  'U', 'V', 'W', 'X', 'Y', 'Z', '0', '1', '2', '3', '4', '5', '6',
+  '7', '8', '9', '.', ',', '(', ')', '+', '-', '*', '/', '=', '$',
+  '<', '>', '@', ';', ':', '\''
+};
+
+
+/* initialise the above arrays */
+void
+mix_init_types (void)
+{
+  guint lt, rt;
+  for (lt = 0; lt < 8; ++lt)
+    for (rt = 0; rt < 8; ++rt) 
+      {
+	guint F = 8 * lt + rt;
+	is_bad_field_[F] = rt < lt || 5 < rt;
+	if ( is_bad_field_[F] )
+	  shift_[F] = 0, mask_[F] = 0;
+	else 
+	  {
+	    guint width = rt - (lt == 0 ? 1 : lt) + 1;
+	    shift_[F] = 6 * (5 - rt);
+	    mask_[F] = ((1L << (6 * width)) - 1) << shift_[F];
+	  } 
+      }
+
+  for ( lt = 0; lt < UCHAR_MAX + 1; ++lt )
+    ascii_to_mix_char_[lt] = NONP_;
+  for ( lt = 0; lt < MIX_CHAR_MAX + 1; ++lt )
+    ascii_to_mix_char_[mix_char_to_ascii_[lt]] = (guchar)lt;
+}
+
+mix_char_t
+mix_ascii_to_char (guchar c)
+{
+  return ascii_to_mix_char_[c];
+}
+
+
+guchar
+mix_char_to_ascii (mix_char_t c)
+{
+  return c > MIX_CHAR_MAX ? NONP_ : mix_char_to_ascii_[c];
+}
+
+
+/*---------------------------- m_word_t --------------------------------- */
+
+/* Create mix_word_t from an array of mix_byte_t */
+mix_word_t
+mix_bytes_to_word (mix_byte_t *bytes, guint byteno)
+{
+  mix_word_t result = 0;
+  guint k;
+  
+  g_return_val_if_fail (bytes != NULL, MIX_WORD_ZERO);
+  g_return_val_if_fail (byteno != 0, MIX_WORD_ZERO);
+  
+  if ( byteno > 5 ) byteno = 5;
+  for ( k = 0; k < byteno; k++ )
+    result |= ((gulong)bytes[k]) << (6*(byteno-k-1));
+
+  return result;
+}
+
+
+/* Field operations */
+mix_word_t /* the specified field or 0 if f is not valid */
+mix_word_get_field (mix_fspec_t f, mix_word_t word)
+{
+  mix_word_t result;
+
+  g_return_val_if_fail (!is_bad_field_[f],MIX_WORD_ZERO);
+  
+  result = ( (word & mask_[f]) >> shift_[f] );
+  if (f < 8)      /* if f is of the form (0:R), retain the sign of word */
+    result |= mix_word_sign (word);
+
+  return result;
+}
+
+
+mix_word_t
+mix_word_set_field (mix_fspec_t f, mix_word_t from, mix_word_t to)
+{
+  mix_word_t result;
+  glong m = mask_[f];
+
+  g_return_val_if_fail (!is_bad_field_[f],to);
+  
+  if (f < 8)      /* if F is of the form (0:R), use the sign of -from- */
+    result =  (to & ~m & ~MIX_WORD_SIGN_BIT) 
+      | ((from /*<< shift_[f]*/) & m) | mix_word_sign (from);
+  else
+    result = (to & ~m) | ((from /*<< shift_[f]*/) & m);
+  
+  return result;
+}
+
+mix_word_t
+mix_word_store_field (mix_fspec_t f, mix_word_t from, mix_word_t to)
+{
+  mix_word_t result;
+  glong m = mask_[f];
+
+  g_return_val_if_fail (!is_bad_field_[f],to);
+  
+  if (f < 8)      /* if F is of the form (0:R), use the sign of -from- */
+    result =  (to & ~m & ~MIX_WORD_SIGN_BIT) 
+      | ((from << shift_[f]) & m) | mix_word_sign (from);
+  else
+    result = (to & ~m) | ((from << shift_[f]) & m);
+  
+  return result;
+}
+  
+
+
+gboolean
+mix_fspec_is_valid (mix_fspec_t f)
+{
+  return !(is_bad_field_[f]);
+}
+
+mix_byte_t 
+mix_word_get_byte (mix_word_t word,   /* word parsed */ 
+		   guint idx          /* byte: 1 to 5 */	  )
+{
+  mix_byte_t fspec = mix_fspec_new (idx,idx);
+
+  g_return_val_if_fail ((idx > 0 && idx < 6), MIX_BYTE_ZERO);
+  
+  return mix_byte_new (mix_word_get_field (fspec,word));
+}
+
+
+extern void 
+mix_word_set_byte (mix_word_t *into, guint idx,  mix_byte_t value)
+{
+  mix_word_t from = value;
+  mix_byte_t fspec = mix_fspec_new (idx,idx);
+
+  g_return_if_fail (into != NULL);
+  g_return_if_fail (idx > 0 && idx < 6);
+  
+  from <<= shift_[fspec];
+  *into = mix_word_set_field (fspec,from,*into);
+}
+
+/* Arithmetic operations */
+mix_word_t 
+mix_word_add (mix_word_t x, mix_word_t y)
+{
+  static const gulong MIX_WORD_MAX_SIM = 2*MIX_WORD_MAX + 1;
+  
+  gint32 result;
+  if ( mix_word_sign (x) == mix_word_sign (y) )
+    {
+      result = (mix_word_magnitude (x) + mix_word_magnitude (y));
+      if ( result >  MIX_WORD_MAX ) {
+	/* for instance MIX_WORD_MAX + 1 = - MIX_WORD_MAX */
+	result = MIX_WORD_MAX_SIM - result;
+	result |= mix_word_sign (mix_word_negative (x));
+      } else if ( result != 0 )      
+	result |= mix_word_sign (x);
+      /* keep positive sign for 0 so that w - w == -w + w */
+    }
+  else
+    {
+      result = mix_word_magnitude (x) -  mix_word_magnitude (y);
+      if (result < 0)
+	result = -result|mix_word_sign (y);
+      else if (result > 0)
+	result = result|mix_word_sign (x);
+      /* keep positive sign for 0 so that w - w == -w + w */
+    }
+ 
+  g_assert ( result >= 0 );
+  
+  return (mix_word_t)result;
+}
+
+gboolean /* TRUE if overflow */
+mix_word_add_and_carry (mix_word_t x, mix_word_t y,
+			mix_word_t *h, mix_word_t *l)
+{
+  gboolean result;
+    
+  if ( mix_word_sign (x) == mix_word_sign (y) )
+    {
+      guint32 sum = (mix_word_magnitude (x) + mix_word_magnitude (y));
+      if ( sum >  MIX_WORD_MAX ) 
+	{
+	  result = TRUE;
+	  if ( l != NULL ) 
+	    {
+	      *l = sum - MIX_WORD_MAX -1;
+	      *l |= mix_word_sign (x);
+	    }
+	  if ( h != NULL ) 
+	    {
+	      *h = sum >> 30;
+	      *h |= mix_word_sign (x);
+	    }
+	} 
+      else /* sum <= MIX_WORD_MAX */
+	{
+	  result = FALSE;
+	  if ( h != NULL ) *h = 0;
+	  if ( l != NULL ) 
+	    {
+	      *l = sum;
+	      if ( sum != 0 )
+		*l |= mix_word_sign (x);
+	      /* keep positive sign for 0 so that w - w == -w + w */
+	    }
+	}
+    }
+  else /* mix_word_sign (x) != mix_word_sign (y) */
+    {
+      result = FALSE;
+      if ( h != NULL ) *h = 0;
+      if ( l != NULL ) 
+	{
+	  gint32 dif = mix_word_magnitude (x) -  mix_word_magnitude (y);
+	  if ( dif < 0)
+	    *l = (-dif)|mix_word_sign (y);
+	  else if ( dif > 0)
+	    *l = dif|mix_word_sign (x);
+	  else /* keep positive sign for 0 so that w - w == -w + w */
+	    *l = MIX_WORD_ZERO;
+	}
+    }
+ 
+  return result;
+}
+  
+
+void 
+mix_word_mul (mix_word_t x, mix_word_t y, 
+	      mix_word_t *high_word, mix_word_t *low_word)
+{
+  guint32 sign = mix_word_sign (x) ^ mix_word_sign (y);
+  
+  /*
+    x = x0 + x1 * 2 ^ 10 + x2 * 2 ^ 20
+    y = y0 + y1 * 2 ^ 10 + y2 * 2 ^ 20
+    x0, x1, x2, y0, y1, y2 are < 2 ^ 10
+  */
+  guint32 x0 = (x & 0x000003FF);
+  guint32 x1 = (x & 0x000FFC00) >> 10;
+  guint32 x2 = (x & 0x3FF00000) >> 20;
+  guint32 y0 = (y & 0x000003FF);
+  guint32 y1 = (y & 0x000FFC00) >> 10;
+  guint32 y2 = (y & 0x3FF00000) >> 20;
+  
+  /*
+    x * y = partial0 +
+    partial1 * 2 ^ 10 +
+    partial2 * 2 ^ 20 +
+    partial3 * 2 ^ 30 +
+    partial4 * 2 ^ 40
+    partial0 and partial4 are <     2 ^ 20
+    partial1 and partial3 are <     2 ^ 21
+    partial2 is               < 3 * 2 ^ 20
+  */
+  guint32 partial0 = x0 * y0;
+  guint32 partial1 = x0 * y1 + x1 * y0;
+  guint32 partial2 = x0 * y2 + x1 * y1 + x2 * y0;
+  guint32 partial3 = x1 * y2 + x2 * y1;
+  guint32 partial4 = x2 * y2;
+  
+  /*  sum1 has a place value of 1 and is < 2 ^ 32 */
+  guint32 sum1   = partial0 + (partial1 << 10);
+  guint32 carry1 = (sum1 & 0xFFF00000) >> 20;
+  
+  /* sum2 has a place value of 2 ^ 20 and is < 2 ^ 32 */
+  guint32 sum2   = partial2 + (partial3 << 10) + carry1;
+  guint32 carry2 = (sum2 & 0xFFF00000) >> 20;
+  
+  /* sum3 has a place value of 2 ^ 40 and is < 2 ^ 20 */
+  guint32 sum3   = partial4 + carry2;
+  
+  sum1 &= ~0xFFF00000;
+  sum2 &= ~0xFFF00000;
+  
+  /*
+    Now paste the three values back into two.
+  */
+  if ( low_word != NULL ) {
+    *low_word   = sum1 | ((sum2 & 0x000003FF) << 20);
+    *low_word  |= sign;
+  }
+  if ( high_word != NULL ) {
+    *high_word  = ((sum2 & 0x000FFC00) >> 10) | (sum3 << 10);
+    *high_word |= sign;
+  }
+}
+
+
+gboolean 
+mix_word_div (mix_word_t n1, mix_word_t n0, mix_word_t d, 
+	      mix_word_t *quotient, mix_word_t *remainder)
+{
+  gboolean overflow = FALSE;  
+  long magn1 = mix_word_magnitude (n1);
+  long magd = mix_word_magnitude (d);
+  
+  if (magd == 0) 
+    {
+      overflow = TRUE;
+      /* just so they have -some- valid value */
+      if ( quotient != NULL ) *quotient = 0;
+      if ( remainder != NULL )  *remainder = 0;  
+    } 
+  else if (magn1 == 0) 
+    {    /* special-cased for speed */
+      if ( quotient != NULL ) 
+	*quotient = (mix_word_sign (n1) ^ mix_word_sign (d)) 
+	  | (mix_word_magnitude (n0) / magd);
+      if ( remainder != NULL )
+	*remainder = mix_word_sign (n1) | (mix_word_magnitude (n0) % magd);
+    } 
+  else if (magd <= magn1) 
+    {
+      overflow = TRUE;
+      if ( quotient != NULL ) *quotient = 0;
+      if ( remainder != NULL )  *remainder = 0;
+    } 
+  else 
+    {
+      long q = mix_word_magnitude (n0);
+      long r = magn1;
+      unsigned i;
+      for (i = 30; i != 0; --i) {
+	r <<= 1;
+	if ( (q & (1L << 29)) != 0 )
+	  ++r;
+	q = (q << 1) & ((1L << 30) - 1);
+	if (magd <= r)
+	  ++q, r -= magd;
+      }
+      if ( quotient != NULL )
+	*quotient = (mix_word_sign (n1) ^ mix_word_sign (d)) | q;
+      if ( remainder != NULL )
+	*remainder = mix_word_sign(n1) | r;
+    }
+  return overflow;
+}
+
+void 
+mix_word_shift_right (mix_word_t A, mix_word_t X, gulong count, 
+		      mix_word_t *pA, mix_word_t *pX)
+{
+  if ( pX != NULL ) *pX = mix_word_sign (X);
+  if ( pA != NULL ) *pA = mix_word_sign (A);
+  if (count < 5) {
+    if ( pA != NULL )
+      *pA |= mix_word_magnitude (A) >> (6 * count);
+    if ( pX != NULL )
+      *pX |= MIX_WORD_MAX & ( (mix_word_magnitude (X) >> (6 * count)) 
+			      | (A << (30 - 6 * count)) );
+  } else if (count < 10 && pX != NULL)
+    *pX |= mix_word_magnitude (A) >> (6 * count - 30);
+  else
+    ;
+}
+
+
+void 
+mix_word_shift_left (mix_word_t A, mix_word_t X, gulong count, 
+		     mix_word_t *pA, mix_word_t *pX)
+{
+  if ( pX != NULL ) *pX = mix_word_sign (X);
+  if ( pA != NULL ) *pA = mix_word_sign (A);
+  if (count < 5) {
+    if ( pX != NULL ) *pX |= MIX_WORD_MAX & (X << (6 * count));
+    if ( pA != NULL )
+      *pA |= MIX_WORD_MAX & ( (A << (6 * count)) |
+			      (mix_word_magnitude (X) >> (30 - 6 * count)) );
+  } else if (count < 10 && pA != NULL)
+    *pA |= MIX_WORD_MAX & (X << (6 * count - 30));
+  else
+    ;
+}
+
+void 
+mix_word_shift_left_circular (mix_word_t A, mix_word_t X, gulong count, 
+			      mix_word_t *pA, mix_word_t *pX)
+{
+  mix_word_t A1, X1;
+  guint c;
+  
+  count %= 10;
+  A1 = count < 5 ? A : X;
+  X1 = count < 5 ? X : A;
+  c = 6 * (count < 5 ? count : count - 5);
+  if ( pX != NULL )
+    *pX = mix_word_sign (X)
+      | ( MIX_WORD_MAX & (X1 << c) ) | ( mix_word_magnitude (A1) >> (30 - c) );
+  if ( pA != NULL )
+    *pA = mix_word_sign (A)
+      | ( MIX_WORD_MAX & (A1 << c) ) | ( mix_word_magnitude (X1) >> (30 - c) );
+}
+
+void 
+mix_word_shift_right_circular (mix_word_t A, mix_word_t X, gulong count, 
+			       mix_word_t *pA, mix_word_t *pX)
+{
+  mix_word_t A1, X1;
+  guint c;
+  
+  count %= 10;
+  A1 = count < 5 ? A : X;
+  X1 = count < 5 ? X : A;
+  c = 6 * (count < 5 ? count : count - 5);
+  if ( pX != NULL )
+    *pX = mix_word_sign (X)
+      | ( mix_word_magnitude (X1) >> c ) | ( MIX_WORD_MAX & (A1 << (30 - c)) );
+  if ( pA != NULL )
+    *pA = mix_word_sign (A)
+      | ( mix_word_magnitude (A1) >> c ) | ( MIX_WORD_MAX & (X1 << (30 - c)) );
+}
+
+
+/* Printable representation */
+void 
+mix_word_print (mix_word_t word, const char *message)
+{
+  guint k;
+  if ( message ) g_print ("%s ", message);
+  g_print ("%s ", mix_word_sign (word) == 0 ? "+" : "-");
+  for ( k = 1; k < 6; ++k ) {
+    g_print ("%02d ", mix_word_get_byte (word,k));
+  }
+  g_print ("(%010ld)", mix_word_magnitude (word));
+}
+
+/* Conversions between words and shorts */
+mix_short_t
+mix_word_to_short (mix_word_t word)
+{
+  if  ( mix_word_is_negative (word) ) 
+    return ( (word & MIX_SHORT_MAX) | MIX_SHORT_SIGN_BIT );
+  else
+    return (word & MIX_SHORT_MAX);
+}
+
+mix_word_t
+mix_short_to_word (mix_short_t s)
+{
+  if ( mix_short_is_negative (s) )
+    return ((mix_word_t) (mix_short_magnitude (s) | MIX_WORD_SIGN_BIT));
+  else
+    return ((mix_word_t)s);
+}
+
+mix_short_t 
+mix_short_add (mix_short_t x, mix_short_t y)
+{
+  static const guint16 MIX_SHORT_MAX_SIM = 2*MIX_SHORT_MAX + 1;
+  
+  gint16 result;
+  if ( mix_short_sign (x) == mix_short_sign (y) )
+    {
+      result = (mix_short_magnitude (x) + mix_short_magnitude (y));
+      if ( result >  MIX_SHORT_MAX ) {
+	/* for instance MIX_SHORT_MAX + 1 = - MIX_SHORT_MAX */
+	result = MIX_SHORT_MAX_SIM - result;
+	result |= mix_short_sign (mix_short_negative (x));
+      } else if ( result != 0 )      
+	result |= mix_short_sign (x);
+      /* keep positive sign for 0 so that w - w == -w + w */
+    }
+  else
+    {
+      result = mix_short_magnitude (x) -  mix_short_magnitude (y);
+      if (result < 0)
+	result = -result|mix_short_sign (y);
+      else if (result > 0)
+	result = result|mix_short_sign (x);
+      /* keep positive sign for 0 so that w - w == -w + w */
+    }
+ 
+  g_assert ( result >= 0 );
+  
+  return (mix_short_t)result;
+}
+
+
+/* Printable representation */
+void
+mix_short_print (mix_short_t s, const gchar *message)
+{
+  if ( message ) g_print ("%s ", message);
+  g_print ("%s ", mix_short_sign (s) == 0 ? "+" : "-");
+  g_print ("%02d %02d ", mix_byte_new (s>>6), mix_byte_new (s));
+  g_print ("(%04d)", mix_short_magnitude (s));
+}
+
+
+
+
diff --git a/mixlib/mix_types.h b/mixlib/mix_types.h
new file mode 100644
index 0000000..a011d18
--- /dev/null
+++ b/mixlib/mix_types.h
@@ -0,0 +1,283 @@
+/* -*-c-*- --------------- mix_types.h:
+ *  This file contains declarations for the basic types used in MIX:
+ *   mix_byte_t, mix_char_t, mix_short_t and mix_word_t.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIX_TYPES_H
+#define MIX_TYPES_H
+
+#include <glib.h>
+
+/* Initialisation function to be called before using the other
+ * functions in this file
+ */
+extern void
+mix_init_types(void);
+
+
+/*----------------- m_byte_t --------------------------------------------*/
+/* MIX byte type */
+typedef guint8 mix_byte_t;
+
+/* Maximum value stored in an mix_byte_t */
+#define MIX_BYTE_MAX ((1L << 6) - 1)
+
+/* Zero mix byte */
+#define MIX_BYTE_ZERO  ((mix_byte_t)0)
+
+/* Create a mix_byte_t from any native type */
+#define mix_byte_new(x) ((mix_byte_t)((x) & MIX_BYTE_MAX ))
+
+/* Operations */
+/* Addition */
+#define mix_byte_add(x,y) mix_byte_new((x) + (y))
+/* Substraction */
+#define mix_byte_sub(x,y) mix_byte_new((x) - (y))
+/* Product */
+#define mix_byte_mul(x,y) mix_byte_new((x) * (y))
+/* Quotient */
+#define mix_byte_div(x,y) mix_byte_new((x) / (y))
+
+
+/*----------------- mix_char_t --------------------------------------------*/
+/* MIX char type: chars are coded in MIX from 0 to MIX_CHAR_MAX */
+typedef guint8 mix_char_t;
+
+#define MIX_CHAR_MAX 55
+
+/* Conversions for mix_char_t's */
+#define mix_char_to_byte(mchar) mix_byte_new(mchar)
+#define mix_byte_to_char(byte)  ((mix_char_t)(byte&MIX_CHAR_MAX))
+
+extern mix_char_t
+mix_ascii_to_char(guchar c);
+
+extern guchar
+mix_char_to_ascii(mix_char_t c);
+
+
+/*----------------- mix_word_t --------------------------------------------*/
+/*
+ * Represented as a gint32 (glib ensures that this type has 32
+ * bits). Bit 30 is the sign, higher bits are 0, 
+ * and bits 0-29 are the magnitude.
+ * Each MIX 'byte' is a 6-bit substring of the magnitude.
+ */
+typedef guint32  mix_word_t;
+
+/* Maximum value stored in an mix_word_t */
+#define MIX_WORD_MAX ((1L << 30) - 1)
+/* Sign bit in a word */
+#define MIX_WORD_SIGN_BIT    (1L << 30)
+/* Zero mix word */
+#define MIX_WORD_ZERO  ((mix_word_t)0)
+/* Negative zero mix word */
+#define MIX_WORD_MINUS_ZERO  (MIX_WORD_ZERO | MIX_WORD_SIGN_BIT)
+
+
+/* Create a mix_word_t from any native type */
+#define mix_word_new(x)						\
+( (x) < 0							\
+  ? ( MIX_WORD_SIGN_BIT | ((mix_word_t)(-(x)) & MIX_WORD_MAX) )	\
+  : ( (mix_word_t)(x) & MIX_WORD_MAX )				\
+) 
+
+/* Create a mix_word_t from individual bytes */
+#define mix_word_new_b(b1,b2,b3,b4,b5)				\
+((mix_word_t)(mix_byte_new(b5) + (mix_byte_new(b4)<<6) +	\
+	      (mix_byte_new(b3)<<12) + (mix_byte_new(b2)<<18) +	\
+	      (mix_byte_new(b1)<<24)))
+
+/* Create a negative mix_word_t from individual bytes */
+#define mix_word_new_bn(b1,b2,b3,b4,b5) \
+   mix_word_negative(mix_word_new_b(b1,b2,b3,b4,b5))
+
+/* Create mix_word_t from an array of mix_byte_t */
+extern mix_word_t
+mix_bytes_to_word(mix_byte_t *bytes, guint byteno);
+
+/* Access byte within a word */
+extern mix_byte_t /* byte -idx- or MIX_BYTE_ZERO if -idx- out of range */
+mix_word_get_byte(mix_word_t word,   /* word parsed */ 
+		  guint idx          /* byte: 1 to 5 */);
+
+/* Set a byte  within a mix_word_t  */
+extern void 
+mix_word_set_byte(mix_word_t *into,   /* word to be modified */
+		  guint idx,          /* byte: 1 to 5 */
+		  mix_byte_t value    /* byte's value */);
+
+
+/* Operations */
+/* Sign-related definitions */
+#define mix_word_negative(word)      ( (word) ^ MIX_WORD_SIGN_BIT )
+#define mix_word_reverse_sign(word)  ( word ^= MIX_WORD_SIGN_BIT )
+#define mix_word_sign(word)          ( (word) & MIX_WORD_SIGN_BIT )
+#define mix_word_magnitude(word)     ( (word) & (MIX_WORD_SIGN_BIT - 1) )
+#define mix_word_is_positive(word)   ( mix_word_sign(word) == 0 )
+#define mix_word_is_negative(word)   ( mix_word_sign(word) != 0 )
+
+
+/* Arithmetic operations */
+extern mix_word_t 
+mix_word_add(mix_word_t x, mix_word_t y);
+ 
+#define mix_word_sub(x,y)    ( mix_word_add((x),mix_word_negative(y)) )
+
+/* Add two words filling a high word if needed.
+   -high_word- and/or -low_word- can be NULL.
+*/
+extern gboolean /* TRUE if overflow */
+mix_word_add_and_carry(mix_word_t x, mix_word_t y,
+		       mix_word_t *high_word, mix_word_t *low_word);
+
+/* Product, stored in -high_word- and -low_word-, which
+   can be NULL.
+*/
+extern void 
+mix_word_mul(mix_word_t x, mix_word_t y, 
+	     mix_word_t *high_word, mix_word_t *low_word);
+
+/* Division. -quotient- and/or -remainder- can be NULL. */
+extern gboolean /* TRUE if overflow */ 
+mix_word_div(mix_word_t n1, mix_word_t n0, mix_word_t d, 
+	     mix_word_t *quotient, mix_word_t *remainder);
+
+/* Shift operations */
+extern void 
+mix_word_shift_left(mix_word_t A, mix_word_t X, gulong count, 
+		    mix_word_t *pA, mix_word_t *pX);
+extern void 
+mix_word_shift_right(mix_word_t A, mix_word_t X, gulong count, 
+		     mix_word_t *pA, mix_word_t *pX);
+extern void 
+mix_word_shift_left_circular(mix_word_t A, mix_word_t X, gulong count, 
+			     mix_word_t *pA, mix_word_t *pX);
+extern void 
+mix_word_shift_right_circular(mix_word_t A, mix_word_t X, gulong count, 
+			     mix_word_t *pA, mix_word_t *pX);
+
+
+
+
+/*
+ * Fields within a word: a word containing the (L:R)
+ * bytes of the original one. L and R (with 0 <= L <= R < 6)
+ * are specified by a mix_fspec_t F = 8*L + R.
+ */
+typedef guint8 mix_fspec_t;
+
+#define mix_fspec_left(f) ( ((f)>>3) & 7 )
+#define mix_fspec_right(f) ( (f) & 7 )
+#define mix_fspec_new(L,R) ( mix_byte_new(8*(L) + (R)) )
+
+extern gboolean
+mix_fspec_is_valid(mix_fspec_t f);
+
+extern mix_word_t /* the specified field or 0 if f is not valid */
+mix_word_get_field(mix_fspec_t f, mix_word_t word);
+
+extern mix_word_t /* -to- with the field -f- from -from- or -to- 
+		     if -f- is not a valid fspec  */
+mix_word_set_field(mix_fspec_t f, mix_word_t from, mix_word_t to);
+
+/* set field into a zero word */
+#define mix_word_extract_field(fspec,from_word) \
+    mix_word_set_field(fspec,from_word,MIX_WORD_ZERO)
+
+/* Store operation: the no. of bytes determined by -f- is taken
+ * from the right of -from- and stored into -to- in the location
+ *  specified by -f-
+ */
+extern mix_word_t
+mix_word_store_field(mix_fspec_t f, mix_word_t from, mix_word_t to);
+
+
+/* Printable representation */
+extern void 
+mix_word_print(mix_word_t word, const char *message);
+
+
+/*----------------- mix_short_t ------------------------------------------*/
+typedef guint16 mix_short_t;
+
+#define MIX_SHORT_MAX  ((1L << 12) - 1)
+#define MIX_SHORT_SIGN_BIT  ((mix_short_t)(1L << 12))
+#define MIX_SHORT_ZERO ((mix_short_t)0)
+#define MIX_SHORT_MINUS_ZERO (MIX_SHORT_ZERO | MIX_SHORT_SIGN_BIT)
+
+/* Sign-related definitions */
+#define mix_short_negative(s)      ( (s) ^ MIX_SHORT_SIGN_BIT )
+#define mix_short_sign(s)          ( (s) & MIX_SHORT_SIGN_BIT )
+#define mix_short_magnitude(s)     	\
+   ( (s) & (MIX_SHORT_SIGN_BIT - 1) )
+#define mix_short_is_positive(s)   ( mix_short_sign(s) == 0 )
+#define mix_short_is_negative(s)   ( mix_short_sign(s) != 0 )
+
+/* create short from a long */
+#define mix_short_new(val) \
+	((val)>= 0 ? (val)&MIX_SHORT_MAX : mix_short_negative(-(val)))
+
+/* Create shorts from individual bytes */
+#define mix_short_new_b(b1,b2) \
+((mix_short_t)((mix_byte_new(b1)<<6) + mix_byte_new(b2)))
+
+#define mix_short_new_bn(b1,b2) mix_short_negative(mix_short_new_b(b1,b2))
+
+/* Conversions between words and shorts. Arithmetic operations
+   on shorts are not provided but for addition: use words instead.
+*/
+/* Make a short taking word's sign and its two least significant
+   bytes (bytes no. 4 and 5)
+*/
+extern mix_short_t
+mix_word_to_short(mix_word_t word);
+
+extern  mix_word_t
+mix_short_to_word(mix_short_t s);
+
+/* fast conversion (these macros' argument are evaluated twice */
+#define mix_word_to_short_fast(w)					\
+( mix_word_is_negative(w) ?						\
+  ((w) & MIX_SHORT_MAX)|MIX_SHORT_SIGN_BIT : (w)&MIX_SHORT_MAX )
+
+#define mix_short_to_word_fast(s)					     \
+( mix_short_is_negative(s) ?						     \
+(mix_word_t) (mix_short_magnitude(s)|MIX_WORD_SIGN_BIT): (mix_word_t)(s) )
+
+
+extern mix_short_t
+mix_short_add(mix_short_t x, mix_short_t y);
+
+
+/* printable representation */
+extern void
+mix_short_print(mix_short_t s, const gchar *message);
+
+
+
+
+
+#endif /* MIX_TYPES_H */
+
+
+
+
diff --git a/mixlib/mix_vm.c b/mixlib/mix_vm.c
new file mode 100644
index 0000000..7e17979
--- /dev/null
+++ b/mixlib/mix_vm.c
@@ -0,0 +1,445 @@
+/* -*-c-*- ------------------ mix_vm.c :
+ * Implementation of the functions declared in mix_vm.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+#include "mix.h"
+#include "xmix_vm.h"
+
+static void
+vm_reset_ (mix_vm_t *vm)
+{
+  guint k;
+  set_rA_ (vm, MIX_WORD_ZERO);
+  set_rX_ (vm, MIX_WORD_ZERO);
+  set_rJ_ (vm, MIX_WORD_ZERO);
+  for ( k = 1; k < IREG_NO_+1; ++k )
+    set_rI_ (vm, k, MIX_WORD_ZERO);
+  set_over_ (vm, FALSE);
+  set_cmp_ (vm, mix_EQ);
+  set_loc_ (vm, MIX_WORD_ZERO);
+  for ( k = 0; k < MEM_CELLS_NO_; ++k)
+    set_cell_ (vm, k, MIX_WORD_ZERO);
+  halt_ (vm, FALSE);
+  if (vm->symbol_table != NULL )
+    {
+      mix_symbol_table_delete (vm->symbol_table);
+      vm->symbol_table = NULL;
+    }
+  if (vm->line_table != NULL)
+    {
+      g_tree_destroy (vm->line_table);
+      vm->line_table = NULL;
+    }
+  bp_clear_all_ (vm);
+}
+
+
+/* Create/destroy a mix vm */
+mix_vm_t *
+mix_vm_new (void)
+{
+  int i;
+  
+  mix_vm_t *vm = g_new (struct mix_vm_t,1);
+  g_return_val_if_fail (vm != NULL, NULL);
+  vm->line_table = NULL;
+  vm->symbol_table = NULL;
+  
+  for (i = 0; i < BD_NO_; ++i)
+    vm->devices[i] = NULL;
+    
+  vm_reset_ (vm);
+  return vm;
+}
+
+void
+mix_vm_delete (mix_vm_t * vm)
+{
+  int i;
+  
+  if (vm->line_table != NULL) g_tree_destroy (vm->line_table);
+  if (vm->symbol_table != NULL) mix_symbol_table_delete (vm->symbol_table);
+  for (i = 0; i < BD_NO_; ++i)
+    mix_device_delete (vm->devices[i]);
+  g_free (vm);
+}
+
+/* Reset a vm  (set state as of a newly created one) */
+void
+mix_vm_reset (mix_vm_t * vm)
+{
+  g_return_if_fail (vm != NULL);
+  vm_reset_ (vm);
+}
+
+/* Set start address for execution */
+void
+mix_vm_set_start_addr (mix_vm_t *vm, mix_address_t addr)
+{
+  g_return_if_fail (vm != NULL);
+  set_loc_ (vm, addr);
+}
+
+/* Access to the vm's registers */
+mix_word_t
+mix_vm_get_rA (const mix_vm_t *vm)
+{
+  g_return_val_if_fail (vm != NULL, MIX_WORD_ZERO);
+  return get_rA_ (vm);
+}
+
+mix_word_t
+mix_vm_get_rX (const mix_vm_t *vm)
+{
+  g_return_val_if_fail (vm != NULL, MIX_WORD_ZERO);
+  return get_rX_ (vm);
+}
+
+mix_short_t
+mix_vm_get_rJ (const mix_vm_t *vm)
+{
+  g_return_val_if_fail (vm != NULL, MIX_SHORT_ZERO);
+  return mix_word_to_short_fast (get_rJ_ (vm));
+}
+
+mix_short_t
+mix_vm_get_rI (const mix_vm_t *vm, guint idx)
+{
+  g_return_val_if_fail (vm != NULL, MIX_SHORT_ZERO);
+  g_return_val_if_fail (IOK_ (idx), MIX_SHORT_ZERO);
+  return mix_word_to_short_fast (get_rI_ (vm, idx));
+}
+
+void 
+mix_vm_set_rA (mix_vm_t *vm, mix_word_t value)
+{
+  g_return_if_fail (vm != NULL);
+  set_rA_ (vm, value);
+}
+
+void
+mix_vm_set_rX (mix_vm_t *vm, mix_word_t value)
+{
+  g_return_if_fail (vm != NULL);
+  set_rX_ (vm, value);
+}
+
+void 
+mix_vm_set_rJ (mix_vm_t *vm, mix_short_t value)
+{
+  g_return_if_fail (vm != NULL);
+  g_return_if_fail (mix_short_is_positive (value));
+  set_rJ_ (vm, mix_short_to_word_fast (value));
+}
+
+void 
+mix_vm_set_rI (mix_vm_t *vm, guint idx, mix_short_t value)
+{
+  g_return_if_fail (vm != NULL);
+  g_return_if_fail (IOK_ (idx));
+  set_rI_ (vm, idx, mix_short_to_word_fast (value));
+}
+
+/* Access to the comparison flag and overflow toggle */
+mix_cmpflag_t
+mix_vm_get_cmpflag (const mix_vm_t *vm)
+{
+  g_return_val_if_fail (vm != NULL, mix_EQ);
+  return get_cmp_ (vm);
+}
+
+void
+mix_vm_set_cmpflag (mix_vm_t *vm, mix_cmpflag_t value)
+{
+  g_return_if_fail (vm != NULL);
+  set_cmp_ (vm, value);
+}
+
+gboolean
+mix_vm_get_overflow (const mix_vm_t *vm)
+{
+  g_return_val_if_fail (vm != NULL, TRUE);
+  return get_over_ (vm);
+}
+
+void
+mix_vm_set_overflow (mix_vm_t *vm, gboolean value)
+{
+  g_return_if_fail (vm != NULL);
+  set_over_ (vm, value);
+}
+
+void
+mix_vm_toggle_overflow (mix_vm_t *vm)
+{
+  g_return_if_fail (vm != NULL);
+  set_over_ (vm, !get_over_ (vm));
+}
+
+/* Access to memory cells */
+mix_word_t
+mix_vm_get_addr_contents (const mix_vm_t *vm, mix_address_t addr)
+{
+  g_return_val_if_fail (vm != NULL, MIX_WORD_ZERO);
+  g_return_val_if_fail (MEMOK_ (addr), MIX_WORD_ZERO);
+  return get_cell_ (vm, addr);
+}
+
+void
+mix_vm_set_addr_contents (mix_vm_t *vm, mix_address_t addr, mix_word_t value)
+{
+  g_return_if_fail (vm != NULL);
+  g_return_if_fail (MEMOK_ (addr));
+  set_cell_ (vm, addr, value);
+}
+
+gboolean
+mix_vm_is_halted (const mix_vm_t *vm)
+{
+  return is_halted_ (vm);
+}
+
+/* Execution of instructions */
+gboolean /* TRUE if success */
+mix_vm_exec_ins (mix_vm_t *vm, const mix_ins_t *ins)
+{
+  g_return_val_if_fail (vm != NULL, FALSE);
+  g_return_val_if_fail (ins != NULL, FALSE);
+  return (*ins_handlers_[ins->opcode]) (vm,ins);
+}
+
+/* comparison function for the line table tree */
+static gint
+cmp_lineno_ (gconstpointer a, gconstpointer b)
+{
+  return GPOINTER_TO_UINT (a) - GPOINTER_TO_UINT (b);
+}
+
+gboolean
+mix_vm_load_file (mix_vm_t *vm, const gchar *name)
+{
+  mix_code_file_t *file;
+  mix_ins_desc_t ins;
+  
+  g_return_val_if_fail (vm != NULL, FALSE);
+  file = mix_code_file_new_read (name);
+  if (file == NULL) return FALSE;
+  vm_reset_ (vm);
+  if ( mix_code_file_is_debug (file) )
+    {
+      vm->symbol_table = mix_code_file_get_symbol_table (file);
+      vm->line_table = g_tree_new (cmp_lineno_);
+    }
+  while ( mix_code_file_get_ins (file, &ins) ) 
+    {
+      set_cell_ (vm, ins.address, ins.ins);
+      if ( vm->line_table != NULL )
+	g_tree_insert (vm->line_table, 
+		       GUINT_TO_POINTER (ins.lineno),
+		       GUINT_TO_POINTER ((guint)ins.address));
+    }
+  set_loc_ (vm, mix_code_file_get_start_addr (file));
+  set_start_ (vm, get_loc_ (vm));
+  mix_code_file_delete (file);
+  
+  return TRUE;
+}
+
+const mix_symbol_table_t *
+mix_vm_get_symbol_table (const mix_vm_t *vm)
+{
+  g_return_val_if_fail (vm != NULL, NULL);
+  return vm->symbol_table;
+}
+
+mix_address_t 
+mix_vm_get_prog_count (const mix_vm_t *vm)
+{
+  g_return_val_if_fail (vm != NULL, MIX_SHORT_ZERO);
+  return get_loc_ (vm);
+}
+
+/* continue execution of instructions in memory */
+int
+mix_vm_run (mix_vm_t *vm)
+{
+  mix_ins_t ins;
+  g_return_val_if_fail (vm != NULL, MIX_VM_ERROR);
+  
+  if ( is_halted_ (vm) )
+    {
+      reset_loc_ (vm);	/* set current location to start address */
+      halt_ (vm, FALSE);
+    }
+  
+  while ( !is_halted_ (vm) )
+    {
+      mix_word_to_ins_uncheck (get_cell_ (vm, get_loc_ (vm)), ins);
+      if ( !(*ins_handlers_[ins.opcode]) (vm,&ins) ) 
+	return MIX_VM_ERROR;
+      if (bp_is_set_ (vm, get_loc_ (vm)))
+	return MIX_VM_BREAK;
+    }
+  return MIX_VM_HALT;
+}
+
+/* execute next memory instruction */
+int
+mix_vm_exec_next (mix_vm_t *vm)
+{
+  mix_ins_t ins;
+  g_return_val_if_fail (vm != NULL, MIX_VM_ERROR);
+  if ( is_halted_ (vm) ) return MIX_VM_HALT;
+  mix_word_to_ins_uncheck (get_cell_ (vm, get_loc_ (vm)), ins);
+  if (!(*ins_handlers_[ins.opcode]) (vm, &ins))
+    return MIX_VM_ERROR;
+  return MIX_VM_BREAK;
+}
+
+/* Breakpoints */
+typedef struct
+{
+  mix_address_t address;
+  gulong lineno;
+} fline_t;
+
+static int
+find_break_ (gpointer key, gpointer value, gpointer data)
+{
+  fline_t *fl = (fline_t *)data;
+  
+  if ( mix_short_new (GPOINTER_TO_UINT (value)) == fl->address )
+    {
+      fl->lineno = GPOINTER_TO_UINT (key);
+      return TRUE;
+    }
+  return FALSE;
+}
+
+gulong
+mix_vm_get_break_lineno (const mix_vm_t *vm)
+{
+  fline_t fl;
+  
+  g_return_val_if_fail (vm != NULL, 0);
+  if (vm->line_table == NULL) return 0;
+  fl.lineno = 0;
+  fl.address = get_loc_ (vm);
+  g_tree_traverse (vm->line_table, find_break_, G_IN_ORDER, (gpointer) &fl);
+  return fl.lineno;
+}
+
+typedef struct 
+{
+  mix_vm_t *vm;
+  guint lineno;
+  gint result;
+} bp_traverse_t;
+
+static gint
+set_break_ (gpointer key, gpointer value, gpointer data)
+{
+  bp_traverse_t *tr = (bp_traverse_t *)data;
+  if (GPOINTER_TO_UINT (key) >= tr->lineno)
+    {
+      bp_set_ (tr->vm, mix_short_new (GPOINTER_TO_UINT (value)));
+      tr->lineno = GPOINTER_TO_UINT (key);
+      tr->result = MIX_VM_BP_OK;
+      return TRUE;
+    }
+  return FALSE;
+}
+
+gint /* if >0 the line no. of the break point */
+mix_vm_set_breakpoint (mix_vm_t *vm, guint lineno)
+{
+  bp_traverse_t tr;
+  
+  g_return_val_if_fail (vm != NULL, MIX_VM_BP_ERROR);
+  if (!vm->line_table) return MIX_VM_BP_NDEBUG;
+  tr.lineno = lineno;
+  tr.vm = vm;
+  tr.result = MIX_VM_BP_INV_LINE;
+  g_tree_traverse (vm->line_table, set_break_, G_IN_ORDER, (gpointer)&tr);
+  if (tr.result == MIX_VM_BP_OK)
+    return tr.lineno;
+  else
+    return tr.result;
+}
+
+gint
+mix_vm_set_breakpoint_address (mix_vm_t *vm, guint address) 
+{
+  g_return_val_if_fail (vm != NULL, MIX_VM_BP_ERROR);
+  if (address >= MIX_VM_CELL_NO)
+    return MIX_VM_BP_INV_ADDRESS;
+  else
+    bp_set_ (vm, mix_short_new (address));
+  return MIX_VM_BP_OK;
+}
+
+static gint
+clear_break_ (gpointer key, gpointer value, gpointer data)
+{
+  bp_traverse_t *tr = (bp_traverse_t *)data;
+  if (GPOINTER_TO_UINT (key) == tr->lineno)
+    {
+      bp_clear_ (tr->vm, mix_short_new (GPOINTER_TO_UINT (value)));
+      tr->result = MIX_VM_BP_OK;
+      return TRUE;
+    }
+  else if (GPOINTER_TO_UINT (key) > tr->lineno)
+    return TRUE;
+  
+  return FALSE;
+}
+
+gint /* one of MIX_VM_BP_ */
+mix_vm_clear_breakpoint (mix_vm_t *vm, guint lineno)
+{
+  bp_traverse_t tr;
+  
+  g_return_val_if_fail (vm != NULL, MIX_VM_BP_ERROR);
+  if (!vm->line_table) return MIX_VM_BP_NDEBUG;
+  tr.lineno = lineno;
+  tr.vm = vm;
+  tr.result = MIX_VM_BP_INV_LINE;
+  g_tree_traverse (vm->line_table, clear_break_, G_IN_ORDER, (gpointer)&tr);
+  return tr.result;
+}
+
+gint
+mix_vm_clear_breakpoint_address (mix_vm_t *vm, guint address) 
+{
+  g_return_val_if_fail (vm != NULL, MIX_VM_BP_ERROR);
+  if (address >= MIX_VM_CELL_NO)
+    return MIX_VM_BP_INV_ADDRESS;
+  else
+    bp_clear_ (vm, mix_short_new (address));
+  return MIX_VM_BP_OK;
+}
+
+void
+mix_vm_clear_all_breakpoints (mix_vm_t *vm)
+{
+  g_return_if_fail (vm != NULL);
+  bp_clear_all_ (vm);
+}
+
diff --git a/mixlib/mix_vm.h b/mixlib/mix_vm.h
new file mode 100644
index 0000000..6ddbb8e
--- /dev/null
+++ b/mixlib/mix_vm.h
@@ -0,0 +1,171 @@
+/* ---------------------- mix_vm.h :
+ * Types and functions implementing the MIX virtual machine
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIX_VM_H
+#define MIX_VM_H
+
+#include "mix_types.h"
+#include "mix_ins.h"
+#include "mix_code_file.h"
+#include "mix_symbol_table.h"
+
+/* Comparison flag */
+typedef enum { mix_LESS, mix_EQ, mix_GREAT } mix_cmpflag_t;
+
+/* Number of memory cells in the virtual machine */
+enum { MIX_VM_CELL_NO = 4000 };
+
+/* Opaque type for the mix virtual machine */
+typedef struct mix_vm_t mix_vm_t;
+
+/* Create/destroy a mix vm */
+extern mix_vm_t *
+mix_vm_new(void);
+
+extern void
+mix_vm_delete(mix_vm_t * vm);
+
+/* Reset a vm (set state as of a newly created one) */
+extern void
+mix_vm_reset(mix_vm_t * vm);
+
+/* Set start address for execution */
+extern void
+mix_vm_set_start_addr(mix_vm_t *vm, mix_address_t addr);
+
+/* Access to the vm's registers */
+extern mix_word_t
+mix_vm_get_rA(const mix_vm_t *vm);
+
+extern mix_word_t
+mix_vm_get_rX(const mix_vm_t *vm);
+
+extern mix_short_t
+mix_vm_get_rJ(const mix_vm_t *vm);
+
+extern mix_short_t
+mix_vm_get_rI(const mix_vm_t *vm, guint idx);
+
+extern void 
+mix_vm_set_rA(mix_vm_t *vm, mix_word_t value);
+
+extern void
+mix_vm_set_rX(mix_vm_t *vm, mix_word_t value);
+
+extern void 
+mix_vm_set_rJ(mix_vm_t *vm, mix_short_t value);
+
+extern void 
+mix_vm_set_rI(mix_vm_t *vm, guint idx, mix_short_t value);
+
+
+/* Access to the comparison flag and overflow toggle */
+extern mix_cmpflag_t
+mix_vm_get_cmpflag(const mix_vm_t *vm);
+
+extern void
+mix_vm_set_cmpflag(mix_vm_t *vm, mix_cmpflag_t value);
+
+extern gboolean
+mix_vm_get_overflow(const mix_vm_t *vm);
+
+extern void
+mix_vm_set_overflow(mix_vm_t *vm, gboolean value);
+
+extern void
+mix_vm_toggle_overflow(mix_vm_t *vm);
+
+extern gboolean
+mix_vm_is_halted(const mix_vm_t *vm);
+
+/* Access to memory cells */
+extern mix_word_t
+mix_vm_get_addr_contents(const mix_vm_t *vm, mix_address_t addr);
+
+extern void
+mix_vm_set_addr_contents(mix_vm_t *vm, mix_address_t addr, mix_word_t value);
+
+/* Execution of instructions and programs */
+extern gboolean /* TRUE if success */
+mix_vm_exec_ins(mix_vm_t *vm, const mix_ins_t *ins);
+
+/* Load a code file into memory (-name- does not need the default extension) 
+ * resetting the vm's state
+ */
+extern gboolean
+mix_vm_load_file(mix_vm_t *vm, const gchar *name);
+
+/* Get symbol table of loaded file */
+extern const mix_symbol_table_t *
+mix_vm_get_symbol_table (const mix_vm_t *vm);
+
+/* Get current program counter */
+extern mix_address_t 
+mix_vm_get_prog_count (const mix_vm_t *vm);
+
+/* continue execution of instructions in memory */
+/* Possible outcomes */
+enum {
+  MIX_VM_ERROR,		/* error executing instructions */
+  MIX_VM_BREAK,		/* breakpoint found */
+  MIX_VM_HALT		/* end of execution */
+};
+
+extern int
+mix_vm_run (mix_vm_t *vm);
+
+/* execute next memory instruction */
+extern int
+mix_vm_exec_next (mix_vm_t *vm);
+
+/* get the line no. of the last break or 0 if not found */
+extern gulong
+mix_vm_get_break_lineno (const mix_vm_t *vm);
+
+/* Breakpoints */
+/* possible error outcomes */
+enum {
+  MIX_VM_BP_ERROR = -4,		/* internal error */
+  MIX_VM_BP_NDEBUG = -3,	/* no debug info */
+  MIX_VM_BP_INV_ADDRESS = -2,   /* address out of range */
+  MIX_VM_BP_INV_LINE = -1,	/* invalid line no. */
+  MIX_VM_BP_OK = 0		/* success */
+};
+
+extern gint /* if >0 the line no. of the break point */
+mix_vm_set_breakpoint (mix_vm_t *vm, guint lineno);
+
+extern gint /* one of MIX_VM_BP_ */
+mix_vm_set_breakpoint_address (mix_vm_t *vm, guint address);
+
+extern gint /* one of MIX_VM_BP_ */
+mix_vm_clear_breakpoint (mix_vm_t *vm, guint lineno);
+
+extern gint /* one of MIX_VM_BP_ */
+mix_vm_clear_breakpoint_address (mix_vm_t *vm, guint address) ;
+
+extern void
+mix_vm_clear_all_breakpoints (mix_vm_t *vm);
+
+
+#endif /* MIX_VM_H */
+
diff --git a/mixlib/mix_vm_dump.c b/mixlib/mix_vm_dump.c
new file mode 100644
index 0000000..33b5c38
--- /dev/null
+++ b/mixlib/mix_vm_dump.c
@@ -0,0 +1,194 @@
+/* ---------------------- mix_vm_dump.c :
+ * Implementation of the functions declared in mix_vm_dump.h
+ * ------------------------------------------------------------------
+** Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+**  
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU General Public License as published by
+** the Free Software Foundation; either version 2 of the License, or
+** (at your option) any later version.
+**  
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+** GNU General Public License for more details.
+**  
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+**  
+*/
+
+#include "mix.h"
+#include <unistd.h>
+#include "xmix_vm.h"
+#include "mix_vm_dump.h"
+
+/* Create/destroy a dump context */
+mix_dump_context_t *
+mix_dump_context_new(gint fd, mix_address_t begin, mix_address_t end,
+		     guint32 options)
+{
+  mix_dump_context_t *result = NULL;
+  GIOChannel *channel = NULL;
+  
+  if ( fd == MIX_DUMP_DEF_CHANNEL ) fd = STDIN_FILENO;
+  channel = g_io_channel_unix_new (fd);
+  g_return_val_if_fail (channel != NULL, NULL);
+  
+  if ( begin > end ) begin = end;
+  if ( end >= MEM_CELLS_NO_ ) end = MEM_CELLS_NO_;
+
+  result = g_new (mix_dump_context_t,1);
+  g_return_val_if_fail (result != NULL, NULL);
+
+  result->options = options;
+  result->begin = begin;
+  result->end = end;
+  result->channel = channel;
+  
+  return result;
+}
+
+void
+mix_dump_context_delete (mix_dump_context_t *dc)
+{
+  g_return_if_fail (dc != NULL);
+  g_io_channel_close (dc->channel);
+  g_free (dc);
+}
+
+gboolean /* TRUE if success */
+mix_dump_context_set_channel (mix_dump_context_t *dc, gint fd)
+{
+  g_return_val_if_fail (dc != NULL, FALSE);
+  g_io_channel_close (dc->channel);
+  dc->channel = g_io_channel_unix_new (fd == MIX_DUMP_DEF_CHANNEL? 
+				       STDERR_FILENO : fd);
+  return ( dc->channel != NULL );
+}
+
+/* Use the dump context */
+#define WORD_FMT_   "%s %02d %02d %02d %02d %02d (%010ld)"
+#define SHORT_FMT_  "%s %02d %02d (%04d)"
+#define WORD_SIGN_(w)  mix_word_is_negative (w)? "-":"+"
+#define SHORT_SIGN_(s) mix_short_is_negative (s)? "-":"+" 
+#define WORD_ABS_(w)   mix_word_magnitude (w)
+#define SHORT_ABS_(s)  mix_short_magnitude (s)
+#define WORD_BYTE_(w,i) mix_byte_new (mix_word_magnitude (w)>>(6*(5-i)))
+#define SHORT_BYTE_(s,i) mix_byte_new (mix_short_magnitude (s)>>(6*(2-i)))
+#define WORD_ARGS_(w)  WORD_SIGN_ (w), WORD_BYTE_ (w,1), WORD_BYTE_ (w,2), \
+	   WORD_BYTE_ (w,3), WORD_BYTE_ (w,4), WORD_BYTE_ (w,5), WORD_ABS_ (w)
+#define SHORT_ARGS_(s) SHORT_SIGN_ (s), SHORT_BYTE_ (s,1), SHORT_BYTE_ (s,2), \
+		       SHORT_ABS_ (s)
+
+static gboolean
+write_buffer_ (const gchar *buf, guint len, GIOChannel *io)
+{
+  guint k, err;
+  
+  while ( len > 0 ) {
+    err = g_io_channel_write (io, (gchar *) buf, len, &k);
+    g_return_val_if_fail (err == G_IO_ERROR_NONE || 
+			  err == G_IO_ERROR_AGAIN, FALSE);
+    len -= k;
+  }
+  return TRUE;
+}
+
+
+
+void
+mix_vm_dump (const mix_vm_t *vm, const mix_dump_context_t *dc)
+{
+  static const guint BUF_LEN = 40;
+  gchar buf[BUF_LEN];
+  guint j, i;
+  
+  g_return_if_fail (vm != NULL);
+  g_return_if_fail (dc != NULL);
+  
+
+  if ( (dc->options & MIX_DUMP_rA) == MIX_DUMP_rA ) 
+    {
+      mix_word_t rA = get_rA_ (vm);
+      guint k = g_snprintf (buf, BUF_LEN, "rA: " WORD_FMT_ "\n", 
+			    WORD_ARGS_ (rA));
+      g_return_if_fail (write_buffer_ (buf, k, dc->channel));
+    }
+
+  if ( (dc->options & MIX_DUMP_rX) == MIX_DUMP_rX ) 
+    {
+      mix_word_t rX = get_rX_ (vm);
+      guint k = g_snprintf (buf, BUF_LEN, "rX: " WORD_FMT_ "\n", 
+			    WORD_ARGS_ (rX));
+      g_return_if_fail (write_buffer_ (buf, k, dc->channel));
+    }
+
+  if ( (dc->options & MIX_DUMP_rJ) == MIX_DUMP_rJ ) 
+    {
+      mix_short_t rJ = get_rJ_ (vm);
+      guint k = g_snprintf (buf, BUF_LEN, "rJ: " SHORT_FMT_ "\n", 
+			    SHORT_ARGS_ (rJ));
+      g_return_if_fail (write_buffer_ (buf, k, dc->channel));
+    }
+  
+  for (j = 0, i = 0; j < IREG_NO_; ++j) 
+    {
+      if ( (dc->options & (MIX_DUMP_rI1<<j)) == (MIX_DUMP_rI1<<j) ) 
+	{
+	  mix_short_t rI = mix_word_to_short_fast (get_rI_ (vm, j+1));
+	  guint k = g_snprintf (buf, BUF_LEN, "rI%d: " SHORT_FMT_ "\t", 
+				j+1, SHORT_ARGS_ (rI));
+	  g_return_if_fail (write_buffer_ (buf, k, dc->channel));
+	  i++;
+	}
+      if ( i%2 == 0 && i != 0 )
+	g_return_if_fail (write_buffer_ ("\n", 1, dc->channel));
+    }
+
+  if ( i%2 == 1 )
+    g_return_if_fail (write_buffer_ ("\n", 1, dc->channel));
+  
+  if ( (dc->options & MIX_DUMP_OVER) == MIX_DUMP_OVER ) 
+    {
+      guint k = g_snprintf (buf, BUF_LEN, _("Overflow: %s\n"),
+			    get_over_ (vm)? "T":"F");
+      g_return_if_fail (write_buffer_ (buf, k, dc->channel));
+    }
+  
+  if ( (dc->options & MIX_DUMP_CMP) == MIX_DUMP_CMP ) 
+    {
+      guint k;
+      const gchar *val = "?";
+      switch (get_cmp_ (vm)) 
+	{
+	case mix_LESS:
+	  val = "L";
+	  break;
+	case mix_GREAT:
+	  val = "G";
+	  break;
+	case mix_EQ:
+	  val = "E";
+	  break;
+	default:
+	  g_assert_not_reached ();
+	  break;
+	}
+      k = g_snprintf (buf, BUF_LEN, _("Cmp: %s\n"), val);
+      g_return_if_fail (write_buffer_ (buf, k, dc->channel));
+    }
+  
+  if ( (dc->options & MIX_DUMP_CELLS) == MIX_DUMP_CELLS ) 
+    {
+      for (j = dc->begin; j < dc->end; ++j) 
+	{
+	  mix_word_t cell = get_cell_ (vm,j);
+	  guint k = g_snprintf (buf, BUF_LEN, "%04d: " WORD_FMT_ "\n", j, 
+				WORD_ARGS_ (cell));
+	  g_return_if_fail (write_buffer_ (buf, k, dc->channel));
+	}
+    }
+}
+
diff --git a/mixlib/mix_vm_dump.h b/mixlib/mix_vm_dump.h
new file mode 100644
index 0000000..b854175
--- /dev/null
+++ b/mixlib/mix_vm_dump.h
@@ -0,0 +1,92 @@
+/* ---------------------- mix_vm_dump.h :
+ * This file declares types and functions for dumping the contents
+ * of a mix virtual machine.
+ * ------------------------------------------------------------------
+** Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+**  
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU General Public License as published by
+** the Free Software Foundation; either version 2 of the License, or
+** (at your option) any later version.
+**  
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+** GNU General Public License for more details.
+**  
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+**  
+*/
+
+
+#ifndef MIX_VM_DUMP_H
+#define MIX_VM_DUMP_H
+
+#include "mix_vm.h"
+
+/* Dump context: a structure defining the properties of dumping */
+typedef struct mix_dump_context_t mix_dump_context_t;
+struct mix_dump_context_t 
+{
+  /* flags activating dumps (see enum below) */
+  guint32 options;
+  /* range of addresses dumped: [begin,end) */
+  mix_address_t begin;
+  mix_address_t end;
+  /* IO channel for dumping */
+  GIOChannel *channel;
+};
+
+/* Flags for activating dumps */
+#define MIX_DUMP_NONE 0
+#define MIX_DUMP_rA  1
+#define MIX_DUMP_rX  (1<<1)
+#define MIX_DUMP_rJ  (1<<2)
+#define MIX_DUMP_rI1 (1<<3)
+#define MIX_DUMP_rI2 (1<<4)
+#define MIX_DUMP_rI3 (1<<5)
+#define MIX_DUMP_rI4 (1<<6)
+#define MIX_DUMP_rI5 (1<<7)
+#define MIX_DUMP_rI6 (1<<8)
+#define MIX_DUMP_rIa MIX_DUMP_rI1|MIX_DUMP_rI2|MIX_DUMP_rI3  \
+		      |MIX_DUMP_rI4|MIX_DUMP_rI5|MIX_DUMP_rI6 
+#define MIX_DUMP_rALL MIX_DUMP_rA|MIX_DUMP_rX|MIX_DUMP_rJ|MIX_DUMP_rIa
+#define MIX_DUMP_OVER (1<<9)
+#define MIX_DUMP_CMP  (1<<10)
+#define MIX_DUMP_CELLS (1<<11)
+#define MIX_DUMP_ALL  MIX_DUMP_rALL|MIX_DUMP_OVER|MIX_DUMP_CMP|MIX_DUMP_CELLS
+#define MIX_DUMP_ALL_NOMEM MIX_DUMP_rALL|MIX_DUMP_OVER|MIX_DUMP_CMP
+
+/* Default output channel (stdout) */
+#define MIX_DUMP_DEF_CHANNEL (-1)
+
+/* Create/destroy a dump context */
+extern mix_dump_context_t *
+mix_dump_context_new(gint fd, mix_address_t begin, mix_address_t end,
+		     guint32 options);
+
+extern void
+mix_dump_context_delete(mix_dump_context_t *dc);
+
+/* Modify an existing dump context */
+#define mix_dump_context_add_opt(dc,opt) ((dc)->options |= (opt))
+#define mix_dump_context_del_opt(dc,opt) ((dc)->options &= ~(opt))
+#define mix_dump_context_set_opt(dc,opt) ((dc)->options = (opt))
+#define mix_dump_context_range(dc,first,last) 	\
+do {						\
+  (dc)->begin = first;				\
+  (dc)->end = last;				\
+} while (FALSE)
+
+extern gboolean /* TRUE if success */
+mix_dump_context_set_channel(mix_dump_context_t *dc, gint fd);
+
+/* Use the dump context */
+extern void
+mix_vm_dump(const mix_vm_t *vm, const mix_dump_context_t *dc);
+
+  
+#endif /* MIX_VM_DUMP_H */
+
diff --git a/mixlib/testsuite/.cvsignore b/mixlib/testsuite/.cvsignore
new file mode 100644
index 0000000..fa47ca5
--- /dev/null
+++ b/mixlib/testsuite/.cvsignore
@@ -0,0 +1,27 @@
+.deps
+Makefile
+Makefile.in
+cardwr.dev
+disk0.dev
+disk1.dev
+disk2.dev
+disk3.dev
+disk4.dev
+disk5.dev
+disk6.dev
+disk7.dev
+mixdevtest
+mixinstest
+mixparsertest
+mixtypest
+mixvminstest
+paper.dev
+printer.dev
+tape0.dev
+tape1.dev
+tape2.dev
+tape3.dev
+tape4.dev
+tape5.dev
+tape6.dev
+tape7.dev
diff --git a/mixlib/testsuite/Makefile.am b/mixlib/testsuite/Makefile.am
new file mode 100644
index 0000000..62d5db6
--- /dev/null
+++ b/mixlib/testsuite/Makefile.am
@@ -0,0 +1,26 @@
+# Copyright (C) 1999 jose antonio ortega ruiz <jaortega@acm.org>
+#  
+# This file is free software; as a special exception the author gives
+# unlimited permission to copy and/or distribute it, with or without 
+# modifications, as long as this notice is preserved.
+# 
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+INCLUDES = -I.. 
+LDADD = $(top_builddir)/mixlib/libmix.a 
+
+check_PROGRAMS = mixtypest mixinstest mixvminstest mixparsertest mixdevtest
+TESTS = $(check_PROGRAMS)
+
+mixtypest_SOURCES = test.h mix_types_t.c
+mixinstest_SOURCES = test.h mix_ins_t.c
+mixvminstest_SOURCES = test.h mix_vm_ins_t.c
+mixparsertest_SOURCES = test.h mix_parser_t.c
+mixdevtest_SOURCES = test.h mix_device_t.c
+
+
+
+
+
diff --git a/mixlib/testsuite/mix_device_t.c b/mixlib/testsuite/mix_device_t.c
new file mode 100644
index 0000000..0b3e066
--- /dev/null
+++ b/mixlib/testsuite/mix_device_t.c
@@ -0,0 +1,76 @@
+/* -*-c-*- -------------- mix_device_t.c :
+ * Implementation of the functions declared in mix_device_t.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+#include <stdlib.h>
+#include <mix_device.h>
+
+/* Define VERBOSE_TEST if you want to get prints of the test */
+/* #define VERBOSE_TEST */
+#include "test.h"
+
+static int S_ = MIX_CHAR_MAX +1;
+
+int 
+main (int argc, char **argv) 
+{
+  mix_device_t *console;
+  size_t s;
+  mix_word_t **block;
+  mix_char_t mchars[S_];
+  gchar chars[S_];
+  int i, j;
+  int bno;
+  
+  
+  INIT_TEST;
+  
+  console = mix_device_new (mix_dev_CONSOLE);
+  s = mix_device_block_size (console);
+  bno = S_/(s*5);
+  if (bno == 0) bno = 1;
+  
+  block = g_new (mix_word_t *, bno);
+  for (i = 0; i < bno; ++i)
+    block[i] = g_new (mix_word_t, s);
+  
+  for (i = 0; i < S_; ++i) {
+    chars[i] = mix_char_to_ascii (i);
+    mchars[i] = mix_ascii_to_char (chars[i]);
+    g_assert (mchars[i] == i);
+  }
+  
+  for (i = 0; i < bno; ++i) {
+    for (j = 0; j < s; ++j) {
+      int n = i*s + 5*j;
+      if (n < S_) 
+	block[i][j] = mix_bytes_to_word (mchars + n, 5);
+      else
+	block[i][j] = 0;
+    }
+  }
+   
+  for (i = 0; i < bno; ++i) {
+    mix_device_write (console, block[i]);
+  }
+  
+  
+  return EXIT_SUCCESS;
+}
diff --git a/mixlib/testsuite/mix_ins_t.c b/mixlib/testsuite/mix_ins_t.c
new file mode 100644
index 0000000..a84d63c
--- /dev/null
+++ b/mixlib/testsuite/mix_ins_t.c
@@ -0,0 +1,79 @@
+/*----------------------- mix_ins_t.c -------------------------------
+ * Tests for mix_ins.h
+ *-------------------------------------------------------------------
+** Copyright (C) 1999  jose antonio ortega ruiz <jaortega@acm.org>
+**  
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU General Public License as published by
+** the Free Software Foundation; either version 2 of the License, or
+** (at your option) any later version.
+**  
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+** GNU General Public License for more details.
+**  
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+**  
+*/
+
+#include <stdlib.h>
+#include <mix_ins.h>
+
+/* Define VERBOSE_TEST if you want to get prints of the test */
+/* #define VERBOSE_TEST */
+#include "test.h"
+
+
+int
+main(int argc, const char**argv)
+{
+  mix_word_t words[6];
+  mix_ins_t ins[3];
+  guint k;
+  
+  INIT_TEST;
+  
+  g_print("\n...ok.\nTesting mix_ins_id_t properties...\n");
+  for ( k = 0; k < mix_INVALID_INS; ++k )
+    {
+      mix_opcode_t c = mix_get_opcode_from_id(k);
+      mix_fspec_t f = mix_get_fspec_from_id(k);
+      mix_ins_id_t id = mix_get_ins_id(c,f);
+      
+      g_print("%02d:%s (%1d:%1d),  ",
+	      c, mix_get_string_from_id(k), 
+	      mix_fspec_left(f), mix_fspec_right(f));
+      if ( (k+1)%3 == 0 ) g_print("\n");
+
+      g_assert(id==k);
+    }
+  
+  g_print("\n...ok.\nTesting mix_ins_t properties...\n");
+  for ( k = 1; k < mix_INVALID_INS; ++k )
+    {
+      g_print("%d ",k);
+      mix_ins_fill_from_id(ins[0], k);
+      g_assert(mix_ins_id_from_ins(ins[0]) == k);
+      ins[0].address = 0x0123;
+      ins[0].index = mix_I2;
+      words[2] = mix_ins_to_word(ins);
+      g_assert(ins[0].address == mix_get_ins_address(words[2]));
+      g_assert(ins[0].index == mix_get_ins_index(words[2]));
+      g_assert(ins[0].fspec == mix_get_ins_fspec(words[2]));
+      g_assert(ins[0].opcode == mix_get_ins_opcode(words[2]));
+      g_assert(mix_word_to_ins(words[2],ins+1) == k);
+      g_assert(ins[0].address == ins[1].address);
+      g_assert(ins[0].index == ins[1].index);
+      g_assert(ins[0].fspec == ins[1].fspec);
+      g_assert(ins[0].opcode == ins[1].opcode);
+    }
+  
+  g_print("\n...ok.\n");
+  
+  
+  
+  return EXIT_SUCCESS;
+}
diff --git a/mixlib/testsuite/mix_parser_t.c b/mixlib/testsuite/mix_parser_t.c
new file mode 100644
index 0000000..6a7bece
--- /dev/null
+++ b/mixlib/testsuite/mix_parser_t.c
@@ -0,0 +1,85 @@
+/* -*-c-*- -------------- mix_parser_t.c :
+ * Test of mix_parser_t
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+
+#include <stdlib.h>
+#include <mix_parser.h>
+
+/* Define VERBOSE_TEST if you want to get prints of the test */
+/* #define VERBOSE_TEST */
+#include "test.h"
+
+static const gchar * const FILES_[] = { "test1" , "taocp145"
+};
+
+static const size_t FILE_NO_ = sizeof(FILES_)/sizeof(FILES_[0]);
+
+static void
+test_code_(const gchar *name)
+{
+  mix_parser_t *parser = mix_parser_new(name);
+  mix_parser_err_t err;
+  mix_code_file_t *code;
+  mix_ins_desc_t ins;
+  
+  g_assert(parser);
+  err =  mix_parser_compile(parser);
+  if ( err != MIX_PERR_OK ) {
+    g_print(mix_parser_err_string(err));
+    g_print("\n");
+  }   
+  g_assert(err == MIX_PERR_OK);
+  err = mix_parser_write_code(parser, name, FALSE);
+  code = mix_code_file_new_read(name);
+  g_assert(code);
+  g_message("%s: Version: %d.%d", name, mix_code_file_major_version(code),
+	    mix_code_file_minor_version(code));
+  mix_short_print(mix_code_file_get_start_addr(code), "Start address: ");
+  g_print("\n");
+  while ( mix_code_file_get_ins(code, &ins) ) {
+    mix_ins_t i;
+    mix_word_to_ins_uncheck(ins.ins, i);
+    mix_short_print(ins.address, "addr: ");
+    g_print(" : ");
+    mix_ins_print(&i);
+    g_print("\n");
+  }
+  
+  mix_parser_delete(parser);
+  mix_code_file_delete(code);
+}
+
+int 
+main(int argc, char **argv)
+{
+  size_t k;
+  
+  INIT_TEST;
+
+  for (k = 0; k < FILE_NO_; ++k)
+    // test_code_(FILES_[k]);
+    ;
+    
+
+  return EXIT_SUCCESS;
+}
+
diff --git a/mixlib/testsuite/mix_types_t.c b/mixlib/testsuite/mix_types_t.c
new file mode 100644
index 0000000..ad8bab7
--- /dev/null
+++ b/mixlib/testsuite/mix_types_t.c
@@ -0,0 +1,361 @@
+/*----------------------- mix_types_t.c -----------------------------
+ * Tests for mix_types.h
+ * ------------------------------------------------------------------
+*
+** Copyright (C) 1999 jose antonio ortega ruiz <jaortega@acm.org>
+**  
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU General Public License as published by
+** the Free Software Foundation; either version 2 of the License, or
+** (at your option) any later version.
+**  
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+** GNU General Public License for more details.
+**  
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+**  
+*/
+
+
+#include <stdlib.h>
+#include <mix_types.h>
+
+/* Define VERBOSE_TEST if you want to get prints of the test */
+/* #define VERBOSE_TEST */
+#include "test.h"
+
+/* compare two words */
+static gboolean
+word_compare_(mix_word_t w1, mix_word_t w2)
+{
+  if ( mix_word_magnitude(w1) == 0 )
+    return ( mix_word_magnitude(w2) == 0 );
+  else
+    return ( w1 == w2 );
+}
+
+ 
+/* create a word from an array of bytes and check the result */
+static void
+test_word_from_bytes_(mix_word_t *word, 
+		     mix_byte_t *bytes, 
+		     unsigned byteno,
+		     const char *message)
+{
+  mix_byte_t r;
+  unsigned int k;
+  
+  *word = mix_bytes_to_word(bytes,byteno);
+  mix_word_print(*word,message);
+  g_print("\n");
+  for ( k = 5-byteno; k < 5; ++k ) {
+    PRINT_BYTE(r = mix_word_get_byte(*word,k+1));
+    g_print(" (k = %d)\n",k);
+    g_assert( r  == bytes[k-5+byteno] );
+  }
+}
+
+
+/* test field access */
+static void
+test_field_access_(mix_fspec_t l, mix_fspec_t r, 
+		   mix_word_t from, mix_word_t to)
+{
+  mix_fspec_t f  = mix_fspec_new(l,r);
+  mix_word_t result;
+  
+  PRINT_BYTE(l); g_print(", ");
+  PRINT_BYTE(r); g_print(", ");
+  PRINT_BYTE(f); g_print("\n  ");
+  mix_word_print(from, "from: ");
+  mix_word_print(to, " to: ");
+  g_assert( mix_fspec_left(f) == l );
+  g_assert( mix_fspec_right(f) == r );
+  result = mix_word_set_field(f,from,to);
+  mix_word_print(result,"\n\tresult: ");
+  g_assert( mix_word_get_field(f,from) == mix_word_get_field(f,result) );
+  g_print("\n");
+}
+
+/* test word addition */
+static void
+test_word_add_(mix_word_t w1, mix_word_t w2)
+{
+  mix_word_t r;
+  
+  r = mix_word_add(w1,w2);
+  mix_word_print(w1,"\n");
+  mix_word_print(w2,NULL);
+  mix_word_print(r," = ");
+  g_assert( word_compare_(mix_word_sub(r,w1), w2) );
+  g_assert( word_compare_(mix_word_sub(r,w2), w1) );
+  /* while asserting the following, take into account that 0 != -0
+     for mix words, although they are logically equivalent
+  */
+  g_assert( word_compare_(mix_word_sub(w1,r), mix_word_negative(w2)) );
+  g_assert( word_compare_(mix_word_sub(w2,r), mix_word_negative(w1)) );
+  g_assert( word_compare_(mix_word_add(w2,w1), r) );
+}
+
+/* test word multiplication */
+static void
+test_word_mul_(mix_word_t w1, mix_word_t w2)
+{
+  mix_word_t h, l, q, r = 0;
+  mix_word_mul(w1,w2,&h,&l);
+  mix_word_print(w1,"\n");
+  mix_word_print(w2,"*");
+  mix_word_print(h,"\n  =");
+  mix_word_print(l,NULL);
+  if ( w1 != 0 ) {
+    g_assert( mix_word_div(h,l,w1,&q,&r) == FALSE );
+    g_assert( mix_word_magnitude(r) == 0 );
+    g_assert( q == w2 );
+  } else {
+    g_assert( mix_word_magnitude(l) == 0 && mix_word_magnitude(h) == 0 );
+  }
+  if ( w2 != 0 ) {
+    g_assert( mix_word_div(h,l,w2,&q,&r) == FALSE );
+    g_assert( mix_word_magnitude(r) == 0 );
+    g_assert( q == w1 );
+  } else {
+    g_assert( mix_word_magnitude(l) == 0 && mix_word_magnitude(h) == 0 );
+  }
+  
+}
+
+/* test word division */
+static void
+test_word_div_(mix_word_t h, mix_word_t l, mix_word_t by) 
+{
+  mix_word_t q,r;
+  gboolean overflow;
+
+  overflow = mix_word_div(h,l,by,&q,&r);
+ 
+  mix_word_print(h,"\n\n");
+  mix_word_print(l,NULL);
+  mix_word_print(by,"\n div by ");
+
+  if ( !overflow ) {
+    mix_word_t h1, l1, h2;
+    mix_word_print(q,"\n q = ");
+    mix_word_print(r,"  r = ");
+    mix_word_mul(by,q,&h1,&l1);
+    mix_word_add_and_carry(l1,r,&h2,&l1);
+    h1 = mix_word_add(h1,h2);
+    g_assert( mix_word_magnitude(r) < mix_word_magnitude(by) );
+    g_assert( word_compare_(h1,h) );
+    g_assert( mix_word_magnitude(l1) == mix_word_magnitude(l) );
+  } else
+    g_print("\n\t = overflow");
+   
+}
+
+static void
+test_mix_char_(void)
+{
+  mix_char_t mchar;
+  guchar achar;
+  guint k;
+  g_print("\nTesting mix_char_t. Table of mix_chars:\n");
+  
+  for (k = 0; k < MIX_CHAR_MAX + 1; ++k) {
+    mchar = k;
+    achar = mix_char_to_ascii(mchar);
+    g_print("%02d: %c, ",k,achar);
+    if ( (k+1)%5 == 0 ) g_print("\n");
+    g_assert( mchar == mix_ascii_to_char(achar) );
+  }
+  g_print("\n");
+}
+
+
+/* main test driver for mix_types.h/c */
+
+int main(int argc, char **argv)
+{
+  unsigned int j,k;
+  mix_byte_t bytes[5] = { 0, 3, 20, 30, 40 };
+  mix_byte_t r;
+  mix_short_t ss[6];
+  mix_word_t words[6];
+  
+  INIT_TEST;
+  
+  g_print("Testing mix_byte_t arithmetics...\n");
+  PRINT_BYTE(bytes[0]);  g_print(", ");
+  PRINT_BYTE(bytes[1]);  g_print(", ");
+  PRINT_BYTE(bytes[2]);  g_print(", ");
+  PRINT_BYTE(bytes[3]);  g_print(", ");
+  PRINT_BYTE(bytes[4]);  g_print("\n");
+  PRINT_BYTE(r = mix_byte_add(bytes[1],bytes[2]));
+  g_print("\n"); g_assert(r == 23);
+  PRINT_BYTE(r = mix_byte_add(bytes[3],bytes[4]));
+  g_print("\n"); g_assert(r == 6);
+  PRINT_BYTE(r = mix_byte_sub(bytes[0],bytes[1]));
+  g_print("\n"); g_assert(r == 61);
+  PRINT_BYTE(r = mix_byte_sub(bytes[4],bytes[3]));
+  g_print("\n"); g_assert(r == 10);
+  PRINT_BYTE(r = mix_byte_sub(bytes[1],bytes[4]));
+  g_print("\n"); g_assert(r == 27);
+  PRINT_BYTE(r = mix_byte_mul(bytes[0],bytes[1]));
+  g_print("\n"); g_assert(r == 0);
+  PRINT_BYTE(r = mix_byte_mul(bytes[1],bytes[2]));
+  g_print("\n"); g_assert(r == 60);
+  PRINT_BYTE(r = mix_byte_mul(bytes[1],bytes[4]));
+  g_print("\n"); g_assert(r == 56);
+  PRINT_BYTE(r = mix_byte_mul(bytes[4],bytes[1]));
+  g_print("\n"); g_assert(r == 56);
+  PRINT_BYTE(r = mix_byte_div(bytes[4],bytes[2]));
+  g_print("\n"); g_assert(r == 2); 
+  PRINT_BYTE(r = mix_byte_div(bytes[3],bytes[2]));
+  g_print("\n"); g_assert(r == 1);
+
+  test_mix_char_();
+
+  g_print("\nTesting word<->short conversions...");
+  words[0] = mix_bytes_to_word(bytes+1,5); 
+  words[1] = mix_word_negative(words[0]);
+  ss[0] = mix_word_to_short(words[0]);
+  ss[1] = mix_word_to_short(words[1]);
+  mix_word_print(words[0],"\nwords[0]=");
+  mix_word_print(words[1],"\nwords[1]=");
+  mix_short_print(ss[0],"\nss[0]=");
+  mix_short_print(ss[1],"\nss[1]=");
+  g_assert(mix_short_is_positive(ss[0]));
+  g_assert(mix_short_is_negative(ss[1]));
+  words[2] = mix_short_to_word(ss[0]);
+  words[3] = mix_short_to_word(ss[1]);
+  mix_word_print(words[2],"\nwords[2]=");
+  mix_word_print(words[3],"\nwords[3]=");
+  g_assert(mix_word_sign(words[0]) == mix_word_sign(words[2]));
+  g_assert(mix_word_sign(words[1]) == mix_word_sign(words[3]));
+  g_assert(mix_short_magnitude(ss[0]) == mix_word_magnitude(words[2]));
+  g_assert(mix_short_magnitude(ss[1]) == mix_word_magnitude(words[3]));
+  g_assert(mix_word_get_byte(words[0],4) == mix_word_get_byte(words[2],4));
+  g_assert(mix_word_get_byte(words[0],5) == mix_word_get_byte(words[2],5));
+  g_assert(mix_word_get_byte(words[1],4) == mix_word_get_byte(words[3],4));
+  g_assert(mix_word_get_byte(words[1],5) == mix_word_get_byte(words[3],5));
+  words[4] = mix_word_extract_field(mix_fspec_new(4,5),words[0]);
+  words[5] = mix_word_extract_field(mix_fspec_new(4,5),words[1]);
+  mix_word_reverse_sign(words[5]);
+  g_assert(words[4] == words[2]);
+  g_assert(words[5] == words[3]);
+   
+  g_print("Testing mix_word_t creation and byte access...\n");
+  test_word_from_bytes_(words,bytes,5,"word[0] created from bytes[0-4]");
+  test_word_from_bytes_(words+1,bytes,4,"\nword[1] created from bytes[0-3]");
+  test_word_from_bytes_(words+2,bytes,3,"\nword[2] created from bytes[0-2]");
+  words[3] = mix_word_negative(words[2]);
+  g_assert( mix_word_negative(words[3]) == words[2] );
+  g_assert( mix_word_is_negative(words[3]) && !mix_word_is_negative(words[2]));
+  mix_word_print(words[3],"\nword[3] created from -word[2]");
+  test_word_from_bytes_(words+4,bytes+2,2,"\nword[2] created from bytes[2-3]");
+
+  g_print("\nTesting mix_word_t field access...\n");
+  mix_word_set_byte(words+3,1,12);
+  mix_word_set_byte(words+3,2,58);
+  g_assert( mix_word_get_byte(words[3],1) == 12 );
+  g_assert( mix_word_get_byte(words[3],2) == 58 );
+  test_field_access_(0,5,words[3],words[4]);
+  test_field_access_(1,5,words[3],words[4]);
+  test_field_access_(2,5,words[3],words[4]);
+  test_field_access_(3,5,words[3],words[4]);
+  test_field_access_(4,5,words[3],words[4]);
+  test_field_access_(5,5,words[3],words[4]);
+  test_field_access_(0,0,words[3],words[4]);
+
+  g_print("\n\nTesting mix_word_t arithmetics...\n");
+  words[0] = MIX_WORD_MAX;
+  words[1] = mix_word_negative(words[0]);
+  for ( k = 1; k < 6; ++k ) {
+    mix_word_set_byte(words+2,k,5*k);
+    mix_word_set_byte(words+4,k,10*(5-k));
+    mix_word_set_byte(words+3,k,21 + 3*k);
+  }
+  words[5] = 0;
+  
+  g_print("\n***addition***");
+  for ( k = 0; k < 6; ++k )
+    for ( j = 0; j <= k; ++j ) {
+      test_word_add_(words[k],mix_word_negative(words[j]));
+      test_word_add_(words[k],words[j]);
+    }
+  g_print("\n***product***");
+  for ( k = 0; k < 6; ++k )
+    for ( j = 0; j <= k; ++j ) {
+      test_word_mul_(words[k],words[j]);
+    }
+  g_print("\n***division***");
+  for ( k = 0; k < 6; ++k ) {
+    test_word_div_(words[k],0,words[0]);
+    for ( j = 0; j <= k; ++j ) {
+      test_word_div_(k,words[j],words[j]);
+      test_word_div_(0,mix_word_add(mix_word_magnitude(words[j]),j),words[j]);
+      test_word_div_(mix_word_negative(k),words[j],words[j]);
+    }
+  }
+
+  g_print("\nTesting shift operations...\n");
+  for ( k = 0; k < 10; ++k ) 
+    mix_word_set_byte(words+(k/5),1+(k%5),k+1);
+   
+  mix_word_print(words[0],"A = ");
+  mix_word_print(words[1],"X = ");
+  for ( k = 0; k < 11; ++k ) {
+    mix_word_t A, X;
+    unsigned int m;
+    
+    mix_word_shift_left(words[0],words[1],k,&A,&X);
+    g_print("\nShift left %d:\n",k);
+    mix_word_print(A,"A ");
+    mix_word_print(X,"X ");
+    for ( m = 0; m < 10 - k; ++m )
+      g_assert( mix_word_get_byte( m < 5 ? A:X, (m%5)+1 ) ==
+	      mix_word_get_byte(words[(m+k)/5], ((m+k)%5)+1) );
+    for ( ; m < 10; ++m )
+      g_assert( mix_word_get_byte( m < 5 ? A:X, (m%5)+1 ) == 0 );
+    
+    mix_word_shift_right(words[0],words[1],k,&A,&X);
+    g_print("\nShift right %d:\n",k);
+    mix_word_print(A,"A ");
+    mix_word_print(X,"X ");
+    for ( m = 0; m < k; ++m )
+      g_assert( mix_word_get_byte( m < 5 ? A:X, (m%5)+1 ) == 0 );
+    for ( ; m < 10; ++m )
+      g_assert( mix_word_get_byte( m < 5 ? A:X, (m%5)+1 ) ==
+	      mix_word_get_byte(words[(m-k)/5], ((m-k)%5)+1) );
+    
+    mix_word_shift_left_circular(words[0],words[1],k,&A,&X);
+    g_print("\nShift left circular %d:\n",k);
+    mix_word_print(A,"A ");
+    mix_word_print(X,"X ");
+    for ( m = 0; m < 10 - k; ++m )
+      g_assert( mix_word_get_byte( m < 5 ? A:X, (m%5)+1 ) ==
+	      mix_word_get_byte(words[(m+k)/5], ((m+k)%5)+1) );
+    for ( ; m < 10; ++m )
+      g_assert( mix_word_get_byte( m < 5 ? A:X, (m%5)+1 ) == 
+	      mix_word_get_byte(words[(m-10+k)/5], 1+((m-10+k)%5)) );
+    mix_word_shift_right_circular(A, X, k, &A, &X);
+    g_print("\nRe-shiftting right...\n");
+    mix_word_print(A, "A ");
+    mix_word_print(X, "X ");
+    g_assert(A == words[0]);
+    g_assert(X == words[1]);
+  }
+  
+  
+  g_print("\n");
+  return EXIT_SUCCESS;
+}
+
+  
+
+
+
+
diff --git a/mixlib/testsuite/mix_vm_ins_t.c b/mixlib/testsuite/mix_vm_ins_t.c
new file mode 100644
index 0000000..7f9d001
--- /dev/null
+++ b/mixlib/testsuite/mix_vm_ins_t.c
@@ -0,0 +1,500 @@
+/* ---------------------- mix_vm_ins_t.c :
+ * Tests for the virtual machine instruction handlers.
+ * ------------------------------------------------------------------
+** Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+**  
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU General Public License as published by
+** the Free Software Foundation; either version 2 of the License, or
+** (at your option) any later version.
+**  
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+** GNU General Public License for more details.
+**  
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+**  
+*/
+
+
+#include <stdlib.h>
+/*#define VERBOSE_TEST*/
+#include "test.h"
+#include "mix_vm.h"
+#include "mix_vm_dump.h"
+
+typedef struct 
+{
+  mix_word_t rA_b, rA_a;
+  mix_word_t rX_b, rX_a;
+  mix_short_t rJ_b, rJ_a;
+  mix_short_t rI_b[6], rI_a[6];
+  gboolean over_b, over_a;
+  mix_cmpflag_t cmp_b, cmp_a;
+  mix_address_t begin, end;
+  mix_word_t  *cells_b, *cells_a;
+  const mix_ins_t *ins;
+} test_desc_t;
+
+static void
+set_cells_(test_desc_t *t, mix_address_t begin, mix_address_t end)
+{
+  g_assert(begin <= end);
+  t->begin = begin;
+  t->end = end;
+  t->cells_b = g_new(mix_word_t,end-begin);
+  t->cells_a = g_new(mix_word_t,end-begin);
+}
+
+static void 
+free_cells_(test_desc_t *t)
+{
+  g_assert(t);
+  g_free(t->cells_a);
+  g_free(t->cells_b);
+  t->cells_a = t->cells_b = NULL;
+  t->begin = t->end = 0;
+}
+
+
+static void
+fill_test_desc_(test_desc_t *t, const mix_vm_t *vm, const mix_ins_t *ins)
+{
+  guint k;
+  g_assert(t);
+  g_assert(vm);
+  
+  t->rA_b = t->rA_a = mix_vm_get_rA(vm);
+  t->rX_b = t->rX_a = mix_vm_get_rX(vm);
+  t->rJ_b = t->rJ_a = mix_vm_get_rJ(vm);
+  for ( k = 0; k < 6; ++k )
+    t->rI_b[k] = t->rI_a[k] = mix_vm_get_rI(vm,k+1);
+  t->cmp_b = t->cmp_a = mix_vm_get_cmpflag(vm);
+  t->over_b = t->over_a = mix_vm_get_overflow(vm);
+  
+  for (k = 0; k < t->end-t->begin; ++k)
+    t->cells_a[k] = t->cells_b[k] = 
+      mix_vm_get_addr_contents(vm,t->begin+k);
+  t->ins = ins;
+}
+
+
+static void
+run_test_(test_desc_t *t, mix_vm_t *vm, mix_dump_context_t *dc)
+{
+  guint k;
+  g_assert(t);
+  g_assert(vm);
+    
+  mix_vm_set_rA(vm, t->rA_b);
+  mix_vm_set_rX(vm, t->rX_b);
+  mix_vm_set_rJ(vm, t->rJ_b);
+  for (k = 0; k < 6; ++k) mix_vm_set_rI(vm, k+1, t->rI_b[k]);
+  for (k = t->begin; k < t->end; ++k)
+    mix_vm_set_addr_contents(vm, k, t->cells_b[k-t->begin]);
+  mix_vm_set_cmpflag(vm, t->cmp_b);
+  mix_vm_set_overflow(vm, t->over_b);
+
+  mix_ins_print(t->ins);
+  if (dc) {
+    mix_dump_context_range(dc, t->begin, t->end);
+    mix_vm_dump(vm,dc);
+  }
+  k = mix_vm_exec_ins(vm, t->ins);
+  if (dc) mix_vm_dump(vm, dc);
+  g_assert(k == TRUE);
+  g_assert(mix_vm_get_rA(vm) == t->rA_a);
+  g_assert(mix_vm_get_rX(vm) == t->rX_a);
+  for (k = 0; k < 6; ++k) g_assert(mix_vm_get_rI(vm, k+1) == t->rI_a[k]);
+  g_assert(mix_vm_get_cmpflag(vm) == t->cmp_a);
+  g_assert(mix_vm_get_overflow(vm) == t->over_a);
+  for (k = t->begin; k < t->end; ++k)
+    g_assert(mix_vm_get_addr_contents(vm, k) == t->cells_a[k-t->begin]);
+}
+
+  
+
+static void
+test_arithmetics_(mix_vm_t *vm, mix_dump_context_t *dc)
+{
+  test_desc_t test;
+  mix_ins_t ins;
+
+  g_print("\nTesting arithmetic instructions...\n");
+  mix_vm_reset(vm);
+  mix_ins_fill_from_id(ins,mix_ADD);
+  ins.index = 0;
+  ins.address = 1000;
+  mix_vm_set_rA(vm,mix_word_new_b(19,18,1,2,22));
+  mix_vm_set_addr_contents(vm,1000,mix_word_new_b(1,36,5,0,50));
+  set_cells_(&test,1000,1001);
+  fill_test_desc_(&test,vm,&ins);
+  test.rA_a = mix_word_new_b(20,54,6,3,8);
+  run_test_(&test, vm, dc);
+
+  mix_ins_fill_from_id(ins,mix_SUB);
+  mix_vm_set_rA(vm,mix_word_new_bn(19,18,0,0,9));
+  mix_vm_set_addr_contents(vm,1000,mix_word_new_bn(31,16,2,22,0));
+  fill_test_desc_(&test,vm,&ins);
+  test.rA_a = mix_word_new_b(11,62,2,21,55);
+  run_test_(&test, vm, dc);
+
+  mix_ins_fill_from_id(ins,mix_MUL);
+  mix_vm_set_rA(vm,mix_word_new_b(1,1,1,1,1));
+  mix_vm_set_addr_contents(vm,1000, mix_word_new_b(1,1,1,1,1));
+  fill_test_desc_(&test,vm,&ins);
+  test.rA_a = mix_word_new_b(0,1,2,3,4);
+  test.rX_a = mix_word_new_b(5,4,3,2,1);
+  run_test_(&test, vm, dc);
+
+  ins.fspec = mix_fspec_new(1,1);
+  mix_vm_set_rA(vm,mix_word_new_bn(0,0,0,1,48));
+  mix_vm_set_addr_contents(vm,1000,mix_word_new_bn(2,16,2,22,0));
+  fill_test_desc_(&test,vm,&ins);
+  test.rA_a = MIX_WORD_MINUS_ZERO;
+  test.rX_a = mix_word_new_bn(0,0,0,3,32);
+  run_test_(&test, vm, dc);
+
+  mix_vm_set_rA(vm,mix_word_new_bn(0,0,0,1,48));
+  mix_vm_set_addr_contents(vm,1000,mix_word_new_b(2,0,34,33,1));
+  fill_test_desc_(&test,vm,&ins);
+  test.rA_a = MIX_WORD_MINUS_ZERO;
+  test.rX_a = mix_word_new_bn(0,0,0,3,32);
+  run_test_(&test, vm, dc);
+
+  ins.fspec = mix_fspec_new(0,5);
+  mix_vm_set_rA(vm,mix_word_new_bn(50,0,1,48,4));
+  mix_vm_set_addr_contents(vm,1000,mix_word_new_bn(2,0,0,0,0));
+  fill_test_desc_(&test,vm,&ins);
+  test.rA_a = mix_word_new_b(1,36,0,3,32);
+  test.rX_a = mix_word_new_b(8,0,0,0,0);
+  run_test_(&test, vm, dc);
+
+  mix_ins_fill_from_id(ins,mix_DIV);
+  mix_vm_set_rA(vm,MIX_WORD_ZERO);
+  mix_vm_set_rX(vm,mix_word_new_b(0,0,0,0,17));
+  mix_vm_set_addr_contents(vm,1000, mix_word_new_b(0,0,0,0,3));
+  fill_test_desc_(&test,vm,&ins);
+  test.rA_a = mix_word_new_b(0,0,0,0,5);
+  test.rX_a = mix_word_new_b(0,0,0,0,2);
+  run_test_(&test, vm, dc);
+
+  mix_vm_set_rA(vm,MIX_WORD_ZERO);
+  mix_vm_set_rX(vm,mix_word_new_bn(0,0,0,0,17));
+  mix_vm_set_addr_contents(vm,1000, mix_word_new_b(0,0,0,0,3));
+  fill_test_desc_(&test,vm,&ins);
+  test.rA_a = mix_word_new_b(0,0,0,0,5);
+  test.rX_a = mix_word_new_b(0,0,0,0,2);
+  run_test_(&test, vm, dc);
+
+  mix_vm_set_rA(vm, MIX_WORD_MINUS_ZERO);
+  mix_vm_set_rX(vm, mix_word_new_b(19,19,0,3,1));
+  mix_vm_set_addr_contents(vm,1000, mix_word_new_bn(0,0,0,2,0));
+  fill_test_desc_(&test,vm,&ins);
+  test.rA_a = mix_word_new_b(0,9,41,32,1);
+  test.rX_a = mix_word_new_bn(0,0,0,1,1);
+  run_test_(&test, vm, dc);
+
+  free_cells_(&test);
+}
+
+static void
+test_shift_(mix_vm_t *vm, mix_dump_context_t *dc)
+{
+  test_desc_t test;
+  mix_ins_t ins;
+
+  g_print("Testing shift instructions...\n");
+  mix_vm_reset(vm);
+  set_cells_(&test,0,0);
+  fill_test_desc_(&test,vm,&ins);
+  mix_ins_fill_from_id(ins,mix_SRAX);
+  ins.index = 0;
+  ins.address = 1;
+  test.rA_b = mix_word_new_b(1,2,3,4,5);
+  test.rX_b = mix_word_new_bn(6,7,8,9,10);
+  test.rA_a = mix_word_new_b(0,1,2,3,4);
+  test.rX_a = mix_word_new_bn(5,6,7,8,9);
+  run_test_(&test, vm, dc);
+
+  mix_ins_fill_from_id(ins, mix_SLA);
+  ins.address = 2;
+  fill_test_desc_(&test, vm, &ins);
+  test.rA_a = mix_word_new_b(2,3,4,0,0);
+  run_test_(&test, vm, dc);
+
+  mix_ins_fill_from_id(ins, mix_SRC);
+  ins.address = 4;
+  fill_test_desc_(&test, vm, &ins);
+  test.rA_a = mix_word_new_b(6,7,8,9,2);
+  test.rX_a = mix_word_new_bn(3,4,0,0,5);
+  run_test_(&test, vm, dc);
+
+  mix_ins_fill_from_id(ins, mix_SRA);
+  ins.address = 2;
+  fill_test_desc_(&test, vm, &ins);
+  test.rA_a = mix_word_new_b(0,0,6,7,8);
+  run_test_(&test, vm, dc);
+
+  mix_ins_fill_from_id(ins, mix_SLC);
+  ins.address = 501;
+  fill_test_desc_(&test, vm, &ins);
+  test.rA_a = mix_word_new_b(0,6,7,8,3);
+  test.rX_a = mix_word_new_bn(4,0,0,5,0);
+  run_test_(&test, vm, dc);
+}
+
+static void
+test_spc_(mix_vm_t *vm, mix_dump_context_t *dc)
+{
+  test_desc_t test;
+  mix_ins_t ins;
+
+  g_print("Testing special instructions...\n");
+  mix_vm_reset(vm);
+  set_cells_(&test,0,0);
+  fill_test_desc_(&test,vm,&ins);
+  mix_ins_fill_from_id(ins,mix_NUM);
+  ins.index = 0;
+  ins.address = 0;
+  test.rA_b = mix_word_new_bn(0,0,31,32,39);
+  test.rX_b = mix_word_new_b(37,57,47,30,30);
+  test.rA_a = mix_word_negative(12977700);
+  test.rX_a = test.rX_b;
+  run_test_(&test, vm, dc);
+
+  mix_ins_fill_from_id(ins, mix_INCA); 
+  ins.address = 1; 
+  fill_test_desc_(&test, vm, &ins); 
+  test.rA_a = mix_word_negative(12977699);
+  run_test_(&test, vm, dc);
+
+  mix_ins_fill_from_id(ins, mix_CHAR); 
+  fill_test_desc_(&test, vm, &ins); 
+  test.rA_a = mix_word_new_bn(30,30,31,32,39);
+  test.rX_a = mix_word_new_b(37,37,36,39,39);
+  run_test_(&test, vm, dc);
+  
+  mix_ins_fill_from_id(ins, mix_HLT);
+  fill_test_desc_(&test, vm, &ins);
+  run_test_(&test, vm, dc);
+  g_assert(mix_vm_is_halted(vm));
+  
+}
+
+static void
+test_move_(mix_vm_t *vm, mix_dump_context_t *dc)
+{
+  test_desc_t test;
+  mix_ins_t ins;
+  guint k;
+
+  g_print("Testing move instruction...\n");
+  mix_vm_reset(vm);
+  set_cells_(&test,0,10);
+  fill_test_desc_(&test,vm,&ins);
+  mix_ins_fill_from_id(ins,mix_MOVE);
+  
+  ins.index = 0;
+  ins.address = 0;
+  ins.fspec = 5;
+  for ( k = 0; k < 5; ++k )
+    test.cells_b[k] = test.cells_a[k+5] = test.cells_a[k] =mix_word_new(100*k);
+      
+  test.rI_b[0] = 5;
+  test.rI_a[0] = 10;
+  run_test_(&test,vm,dc);
+  
+  free_cells_(&test);
+}
+
+  
+
+static void
+test_load_(mix_vm_t *vm, mix_dump_context_t *dc)
+{
+  test_desc_t test;
+  mix_ins_t ins;
+  mix_ins_id_t ids[4] = {mix_LDA, mix_LDX, mix_LDAN, mix_LDXN};
+  mix_word_t r_a[14] = { mix_word_new_bn(1,16,3,5,4),
+			mix_word_new_b(1,16,3,5,4),
+			mix_word_new_b(0,0,3,5,4),
+			mix_word_new_bn(0,0,1,16,3),
+			mix_word_new_b(0,0,0,0,5),
+			MIX_WORD_MINUS_ZERO,
+			mix_word_new_b(0,0,0,0,1),
+			mix_word_new_b(1,16,3,5,4),
+			mix_word_new_b(1,16,3,5,4),
+			mix_word_new_b(0,0,3,5,4),
+			mix_word_new_b(0,0,1,16,3),
+			mix_word_new_b(0,0,0,0,5),
+			MIX_WORD_ZERO,
+			mix_word_new_b(0,0,0,0,1)};
+  mix_fspec_t fs[11] = {5,13,29,3,36,0,9,0,0,0,0};
+  mix_address_t a_a[11] = { MIX_SHORT_MINUS_ZERO,
+			    mix_short_new_bn(0,1),
+			    mix_short_new_bn(1,16),
+			    mix_short_new_bn(16,3),
+			    mix_short_new_bn(3,5),
+			    mix_short_new_bn(5,4),
+			    mix_short_new_b(1,16),
+			    mix_short_new_b(16,3),
+			    mix_short_new_b(5,4),
+			    mix_short_new_b(5,4),
+			    mix_short_new_b(3,5)};
+  mix_word_t val = mix_word_new_bn(1,16,3,5,4);
+  gint j;
+    
+  g_print("Testing load instructions...\n");
+  set_cells_(&test,2000,2001);
+  ins.index = 1;
+  ins.address = mix_short_negative(50);
+  
+  mix_vm_reset(vm);
+  mix_vm_set_addr_contents(vm, 2000, val);
+        
+  for (j = 0; j < 4; ++j)
+    {
+      gint k;
+      mix_ins_fill_from_id(ins,ids[j]);
+      for ( k = 0; k < 7; ++k ) {
+	fill_test_desc_(&test,vm,&ins);
+	ins.fspec = fs[k];
+	switch (ids[j]) 
+	  {
+	  case mix_LDA: test.rA_a = r_a[k]; break;
+	  case mix_LDX: test.rX_a = r_a[k]; break;
+	  case mix_LDAN: test.rA_a = r_a[k+7]; break;
+	  case mix_LDXN: test.rX_a = r_a[k+7]; break;
+	  default: g_assert_not_reached();
+	  }
+	test.rI_b[0] = test.rI_a[0] = 2050;
+	run_test_(&test, vm, dc);
+      }
+    }
+  ins.index = 0;
+  ins.address = 2000;
+  fs[0] = 0; fs[1] = 1; fs[2] = 2; fs[3] = 3; fs[4] = 4; fs[5] = 5;
+  fs[6] = 10; fs[7] = 11; fs[8] = 37; fs[9] = 29; fs[10] = 12;
+  
+  mix_vm_reset(vm);
+  mix_vm_set_addr_contents(vm, 2000, val);
+  for ( j = 0; j < 14; j++ )
+    {
+      guint k;
+      if (j == 6 || j == 7 ) continue; /* mix_LDX, mix_LDAN */
+      mix_ins_fill_from_id(ins, mix_LD1 + j);
+      for (k = 0; k < 11; ++k)
+	{
+	  fill_test_desc_(&test, vm, &ins);
+	  ins.fspec = fs[k];
+	  if ( j < 6  )
+	    test.rI_a[j] = a_a[k];
+	  else /* mix_LDiN */
+	    test.rI_a[j-8] = mix_short_magnitude(a_a[k]);
+	  run_test_(&test, vm, dc);
+	}
+    }
+
+  free_cells_(&test);
+}
+
+
+static void
+test_store_(mix_vm_t *vm, mix_dump_context_t *dc)
+{
+  test_desc_t test;
+  mix_ins_t ins;
+  mix_word_t reg = mix_word_new_b(6,7,8,9,0);
+  mix_word_t add = mix_word_new_bn(1,2,3,4,5);
+  mix_word_t addr[6] = { mix_word_new_b(6,7,8,9,0),
+			  mix_word_new_bn(6,7,8,9,0),
+			  mix_word_new_bn(1,2,3,4,0),
+			  mix_word_new_bn(1,0,3,4,5),
+			  mix_word_new_bn(1,9,0,4,5),
+			  mix_word_new_b(0,2,3,4,5)};
+  mix_word_t addri[6] = { mix_word_new_b(0,0,0,9,0),
+			  mix_word_new_bn(0,0,0,9,0),
+			  mix_word_new_bn(1,2,3,4,0),
+			  mix_word_new_bn(1,0,3,4,5),
+			  mix_word_new_bn(1,9,0,4,5),
+			  mix_word_new_b(0,2,3,4,5)};
+  mix_word_t addrz[6] = { mix_word_new_b(0,0,0,0,0),
+			  mix_word_new_bn(0,0,0,0,0),
+			  mix_word_new_bn(1,2,3,4,0),
+			  mix_word_new_bn(1,0,3,4,5),
+			  mix_word_new_bn(1,0,0,4,5),
+			  mix_word_new_b(0,2,3,4,5)};
+  mix_fspec_t fs[6] = {5,13,45,18,19,1};
+  gint i,j;
+
+  g_print("Testing store instructions...\n");
+
+  set_cells_(&test,2000,2001);
+  ins.index = 0;
+  ins.address = 2000;
+  
+  mix_vm_reset(vm);
+  fill_test_desc_(&test,vm,&ins);
+  test.rA_a = test.rA_b = test.rX_a = test.rX_b = reg;
+  test.rJ_a = test.rJ_b = mix_word_to_short(reg);
+  for (j = 0; j < 6; ++j)
+    test.rI_a[j] = test.rI_b[j] = test.rJ_a;
+  test.cells_b[0] = add;
+          
+  for (i = 0; i < 10; ++i)
+    {
+      mix_ins_fill_from_id(ins,mix_STA+i);
+      for (j = 0; j < 6; ++j)
+	{
+	  ins.fspec = fs[j];
+	  if (i == 0 || i == 7 ) /* mix_STA, mix_STX */
+	    test.cells_a[0] = addr[j];
+	  else if ( i < 9 ) /* mix_STi, mix_STJ */
+	    test.cells_a[0] = addri[j];
+	  else /* mix_STZ */
+	    test.cells_a[0] = addrz[j];
+	  run_test_(&test,vm,dc);
+	}
+    }
+  
+  free_cells_(&test);
+}
+
+
+
+int
+main(int argc, const char **argv)
+{
+  mix_vm_t *vm;
+  mix_dump_context_t *dc;
+  
+  INIT_TEST;
+
+  vm = mix_vm_new();
+
+#ifdef VERBOSE_TEST
+  dc = mix_dump_context_new(MIX_DUMP_DEF_CHANNEL, 0, 0, MIX_DUMP_ALL);
+#else
+  dc = NULL;
+#endif
+
+  test_arithmetics_(vm, dc);
+  test_shift_(vm, dc);
+  test_spc_(vm,dc);
+  test_move_(vm,dc);
+  test_load_(vm,dc);
+  test_store_(vm,dc);
+  
+  mix_vm_delete(vm);
+
+#ifdef VERBOSE_TEST
+  mix_dump_context_delete(dc);
+#endif
+
+  return EXIT_SUCCESS;
+}
+
diff --git a/mixlib/testsuite/test.h b/mixlib/testsuite/test.h
new file mode 100644
index 0000000..f71feff
--- /dev/null
+++ b/mixlib/testsuite/test.h
@@ -0,0 +1,44 @@
+/*
+** Copyright (C) 1999 jose antonio ortega ruiz <jaortega@acm.org>
+**  
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU General Public License as published by
+** the Free Software Foundation; either version 2 of the License, or
+** (at your option) any later version.
+**  
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+** GNU General Public License for more details.
+**  
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+**  
+*/
+
+/* Common definitions for test programs */
+
+#ifndef TEST_H
+#define TEST_H
+
+#include <glib.h>
+#include <mix.h>
+
+#define PRINT_BYTE(byte) g_print("%s = %02d",#byte,byte)
+
+#ifdef VERBOSE_TEST /* get printed information  */
+#define INIT_TEST \
+ do { g_set_print_handler(NULL); mix_init_lib(); } while(FALSE);
+#else /* no printed information */
+static void
+dummy_print_f_(const gchar *m)
+{
+  /* no output */
+}
+#define INIT_TEST \
+do { g_set_print_handler(dummy_print_f_); mix_init_lib(); } while(FALSE);
+#endif /* VERBOSE_TEST */
+
+
+#endif /* TEST_H */
diff --git a/mixlib/xmix_io.c b/mixlib/xmix_io.c
new file mode 100644
index 0000000..3c997c9
--- /dev/null
+++ b/mixlib/xmix_io.c
@@ -0,0 +1,57 @@
+/* -*-c-*- ------------------ xmix_io.c :
+ * Implementation of the functions declared in xmix_io.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "xmix_io.h"
+
+const char *io_OPENTYPE_[5] = { "r", "w", "w+", "a", "a+" };
+
+
+/* initialise a mix_iochannel from a file descriptor */
+gboolean
+io_init_from_fdesc_(mix_iochannel_t *ioc, int fdesc)
+{
+  FILE *file;
+  mix_fmode_t mode;
+  int flags = fcntl(fdesc, F_GETFL);
+
+  if ( (flags&O_RDONLY) == O_RDONLY ) 
+    mode = mix_io_READ;
+  else if ( (flags&O_WRONLY) == O_WRONLY )
+    mode = mix_io_WRITE;
+  else if ( (flags&O_RDWR) == O_RDWR )
+    mode = mix_io_RDWRT;
+  else 
+    return FALSE;
+  
+  file = fdopen(fdesc, fmode_to_type_(mode));
+  g_return_val_if_fail(file != NULL, FALSE);
+  
+  io_init_from_file_(ioc, file);
+  
+  return TRUE;
+}
+
+
+
diff --git a/mixlib/xmix_io.h b/mixlib/xmix_io.h
new file mode 100644
index 0000000..ca57a4b
--- /dev/null
+++ b/mixlib/xmix_io.h
@@ -0,0 +1,64 @@
+/* -*-c-*- ------------------ xmix_io.h :
+ * Implementation of mix_iochannel_t and mix_file_t
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef XMIX_IOCHANNEL_H
+#define XMIX_IOCHANNEL_H
+
+#include <stdio.h>
+#include "mix_io.h"
+
+/* the actual definition of mix_iochannel_t */
+struct mix_iochannel_t 
+{
+  FILE *file;
+};
+
+
+extern const char * io_OPENTYPE_[5];
+
+#define fmode_to_type_(mode) ( (mode) < 6 ? io_OPENTYPE_[(mode)]:NULL )
+
+/* initialisation */
+extern gboolean
+io_init_from_fdesc_(mix_iochannel_t *ioc, int fdesc);
+
+#define io_init_from_file_(ioc,f) (ioc)->file = f
+
+#define io_close_(ioc)  fclose((ioc)->file)
+
+/* write/read data */
+#define write_data_(ioc,data,no)  \
+ ( (no) == fwrite((const void*)(data), sizeof(*(data)), (no), (ioc)->file) )
+
+#define read_data_(ioc,data,no)  \
+ ( (no) == fread((void*)(data), sizeof(*(data)), (no), (ioc)->file) )
+
+/* state */
+#define is_eof_(ioc)  ( feof((ioc)->file) != 0 )
+#define is_ready_(ioc) ( ferror((ioc)->file) == 0 )
+
+/* conversions */
+#define io_get_FILE_(ioc)  (MIX_IOCHANNEL(ioc))->file
+
+
+#endif /* XMIX_IOCHANNEL_H */
+
diff --git a/mixlib/xmix_parser.h b/mixlib/xmix_parser.h
new file mode 100644
index 0000000..fee385c
--- /dev/null
+++ b/mixlib/xmix_parser.h
@@ -0,0 +1,96 @@
+/* -*-c-*- ---------------- xmix_parser.h :
+ * Declarations for the implementation of mix_parser_t
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef XMIX_PARSER_H
+#define XMIX_PARSER_H
+
+#include "mix_ins.h"
+#include "mix_file.h"
+#include "mix_symbol_table.h"
+#include "mix_parser.h"
+
+/* mix_parser_t definition */
+struct mix_parser_t 
+{
+  mix_file_t  *in_file;     /* the source file to be compiled */ 
+  mix_symbol_table_t *symbol_table; 
+  mix_symbol_table_t *ls_table;  /* literal strings symbols */
+  guint cur_ls;             /* current literal string symbol */
+  GHashTable *future_refs;  /* a map from symbol name to list of addresses */
+  GTree *ins_table;         /* a table of compiled instructions */
+  mix_address_t loc_count;  /* current memory location during compilation */
+  mix_parser_err_t status;  /* outcome of compilation */
+  guint err_line;           /* line of the last error */
+  guint err_count;          /* no. of errors during compilation */
+  guint warn_count;         /* no. of warnings during compilation */
+  mix_address_t start;      /* start address of the compiled code */
+};
+
+/* each node of the ins_table stores a mix_word_t with the instruction
+   and a source code line (for debugging and listing) 
+*/
+typedef struct ins_node_
+{
+  mix_word_t ins;
+  guint lineno;
+} ins_node_;
+
+
+/* functions to manipulate mix_parser_t during compilation */
+/* symbol table */
+
+/* Define a new symbol with value equal to the current loc_count 
+ * and update previously set refs to this symbol 
+ */
+extern mix_parser_err_t 
+mix_parser_define_symbol_here(mix_parser_t *parser, const gchar *name);
+
+/* Set a reference to future symbol here */
+extern void
+mix_parser_set_future_ref(mix_parser_t *parser, const gchar *name);
+
+/* Redefine the value of a local symbol as the current loc_count */
+extern void
+mix_parser_manage_local_symbol(mix_parser_t *parser, const gchar *name);
+
+/* Literal strings symbols */
+extern void
+mix_parser_define_ls (mix_parser_t *parser, mix_word_t value);
+
+/* Compilation */
+/* Add instruction with address the current loc_count */
+extern void
+mix_parser_add_ins(mix_parser_t *parser, const mix_ins_t *new_ins, 
+		   guint lineno);
+extern void
+mix_parser_add_raw(mix_parser_t *parser, mix_word_t word, guint lineno);
+
+/* Error handling */
+extern void 
+mix_parser_log_error(mix_parser_t *parser, mix_parser_err_t error,
+		     gint lineno, const gchar *comment, gboolean warn);
+
+
+
+
+#endif /* XMIX_PARSER_H */
+
diff --git a/mixlib/xmix_vm.c b/mixlib/xmix_vm.c
new file mode 100644
index 0000000..3fc32ab
--- /dev/null
+++ b/mixlib/xmix_vm.c
@@ -0,0 +1,568 @@
+/* ---------------------- xmix_vm.c :
+ * Implementation of the functions declared in xmix_vm.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+
+#include "xmix_vm.h"
+
+/* auxiliar functions */
+G_INLINE_FUNC mix_address_t
+get_M_(const mix_vm_t *vm, const mix_ins_t *ins);
+G_INLINE_FUNC mix_word_t
+get_V_(const mix_vm_t *vm, const mix_ins_t *ins);
+G_INLINE_FUNC mix_device_t *
+get_dev_ (mix_vm_t *vm, mix_fspec_t type);
+
+G_INLINE_FUNC mix_address_t
+get_M_(const mix_vm_t *vm, const mix_ins_t *ins)
+{
+  if ( ins->index == 0 )
+    return ins->address;
+  else
+    return mix_short_add(ins->address, 
+			 mix_word_to_short_fast(get_rI_(vm, ins->index)));
+}
+
+G_INLINE_FUNC mix_word_t
+get_V_(const mix_vm_t *vm, const mix_ins_t *ins)
+{
+  return mix_word_get_field(ins->fspec, get_cell_(vm, get_M_(vm,ins)));
+}
+
+G_INLINE_FUNC mix_device_t *
+get_dev_ (mix_vm_t *vm, mix_fspec_t type) 
+{
+  if (type >= BD_NO_) return NULL;
+  if (vm->devices[type] == NULL)
+    vm->devices[type] = mix_device_new (type);
+  return vm->devices[type];
+}
+
+/* Instruction handlers */
+
+static gboolean 
+nop_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  g_assert(ins->opcode == mix_opNOP);
+  inc_loc_(vm);
+  return TRUE;
+}
+
+static gboolean 
+add_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  mix_word_t val = get_V_(vm, ins);
+  g_assert(ins->opcode == mix_opADD || ins->opcode == mix_opSUB);
+  if ( ins->opcode == mix_opSUB ) mix_word_reverse_sign(val);
+  if ( mix_word_add_and_carry(get_rA_(vm), val, NULL, &get_rA_(vm)) )
+    set_over_(vm,TRUE);
+  inc_loc_(vm);
+  return TRUE;
+}
+
+
+static gboolean 
+mul_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  g_assert(ins->opcode == mix_opMUL);
+  mix_word_mul(get_rA_(vm), get_V_(vm,ins), &get_rA_(vm), &get_rX_(vm));
+  inc_loc_(vm);
+  return TRUE;
+}
+
+static gboolean 
+div_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  g_assert(ins->opcode == mix_opDIV);
+  if ( mix_word_div(get_rA_(vm), get_rX_(vm), get_V_(vm,ins),
+		    &get_rA_(vm), &get_rX_(vm)) )
+    set_over_(vm,TRUE);
+  inc_loc_(vm);
+  return TRUE;
+}
+
+static gboolean 
+spc_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  g_assert(ins->opcode == mix_opSPC);
+  
+  switch (mix_ins_id_from_ins(*ins)) {
+  case mix_HLT: halt_(vm, TRUE); break;
+  case mix_CHAR:
+    { 
+      guint32 num = mix_word_magnitude(get_rA_(vm));
+      mix_char_t z = mix_ascii_to_char('0');
+      guint i;
+      for (i = 5; 0 < i; --i, num /= 10)
+	mix_word_set_byte(&get_rX_(vm), i, z + num % 10);
+      for (i = 5; 0 < i; --i, num /= 10)
+	mix_word_set_byte(&get_rA_(vm), i, z + num % 10);
+      break;
+    }
+  case mix_NUM: 
+    { 
+      guint i;
+      mix_word_t num = MIX_WORD_ZERO;
+      mix_word_t ten = 10;
+      for (i = 1; i <= 5; ++i) {
+	mix_word_mul(ten, num, NULL, &num);
+	mix_word_add_and_carry(num, mix_word_get_byte(get_rA_(vm),i)%10,
+			       NULL, &num);
+      }
+      for (i = 1; i <= 5; ++i) {
+	mix_word_mul(ten, num, NULL, &num);
+	mix_word_add_and_carry(num, mix_word_get_byte(get_rX_(vm),i)%10,
+			       NULL, &num);
+      }
+      set_rA_(vm,
+	      mix_word_is_negative(get_rA_(vm)) ? mix_word_negative(num):num);
+      break;
+    }
+  default: return FALSE;
+  }
+  inc_loc_(vm);
+  return TRUE;
+}
+
+static gboolean 
+sla_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  mix_short_t n = get_M_(vm,ins);
+  
+  g_assert(ins->opcode == mix_opSLx);
+  g_return_val_if_fail(mix_short_is_positive(n), FALSE);
+  
+  switch ( mix_ins_id_from_ins(*ins) ) {
+  case mix_SLA:
+    mix_word_shift_left(get_rA_(vm), MIX_WORD_ZERO, n, &get_rA_(vm), NULL);
+    break;
+  case mix_SRA:
+    mix_word_shift_right(get_rA_(vm), MIX_WORD_ZERO, n, &get_rA_(vm), NULL);
+    break;
+  case mix_SLAX:
+    mix_word_shift_left(get_rA_(vm), get_rX_(vm), n, 
+			&get_rA_(vm), &get_rX_(vm));
+    break;
+  case mix_SRAX:
+    mix_word_shift_right(get_rA_(vm), get_rX_(vm), n, 
+			&get_rA_(vm), &get_rX_(vm));
+    break;
+  case mix_SLC:
+    mix_word_shift_left_circular(get_rA_(vm), get_rX_(vm), n, 
+				 &get_rA_(vm), &get_rX_(vm));
+    break;
+  case mix_SRC:
+    mix_word_shift_right_circular(get_rA_(vm), get_rX_(vm), n, 
+				  &get_rA_(vm), &get_rX_(vm));
+    break;
+  default:
+    return FALSE;
+  }
+  
+  inc_loc_(vm);
+  return TRUE;
+}
+
+static gboolean 
+mov_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  mix_short_t from = get_M_(vm,ins), 
+    to = mix_word_to_short_fast(get_rI_(vm,1));
+  guint k, delta = ins->fspec;
+  
+  g_assert(ins->opcode == mix_opMOVE);
+  g_return_val_if_fail(mix_short_is_positive(from), FALSE);
+  g_return_val_if_fail(mix_short_is_positive(to), FALSE);
+  g_return_val_if_fail(MEMOK_(from + delta -1), FALSE);
+  g_return_val_if_fail(MEMOK_(to + delta - 1), FALSE);
+  
+  for (k = 0; k < delta; ++k)
+    set_cell_(vm, to+k, get_cell_(vm, from+k));
+  set_rI_(vm, 1, to+delta);
+  inc_loc_(vm);
+  return TRUE;
+}
+
+static gboolean
+lda_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  gint r = 0;
+  mix_word_t val;
+  mix_ins_id_t id = mix_ins_id_from_ins(*ins);
+    
+  g_assert(id >= mix_LDA && id <= mix_LDXN);
+  
+  val = get_V_(vm, ins);
+  if ( id > mix_LDX && mix_fspec_left(ins->fspec) == 0) 
+    mix_word_reverse_sign(val);
+  if ( (id > mix_LDA && id < mix_LDX) || (id > mix_LDAN && id < mix_LDXN) )
+    /* Bytes 1-3 of I regs are always null */
+    val = mix_word_set_field(mix_fspec_new(1,3),MIX_WORD_ZERO,val);
+        
+  switch (id) {
+  case mix_LDA: case mix_LDAN: r = A_; break;
+  case mix_LDX: case mix_LDXN: r = X_; break;
+  case mix_LD1: case mix_LD1N: r = I1_; break;
+  case mix_LD2: case mix_LD2N: r = I2_; break;
+  case mix_LD3: case mix_LD3N: r = I3_; break;
+  case mix_LD4: case mix_LD4N: r = I4_; break;
+  case mix_LD5: case mix_LD5N: r = I5_; break;
+  case mix_LD6: case mix_LD6N: r = I6_; break;
+  default: g_assert_not_reached();
+  }
+  set_reg_(vm, r, val);
+  inc_loc_(vm);
+  return TRUE;
+}
+
+
+static gboolean
+sta_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  mix_address_t addr = get_M_(vm, ins);
+  mix_ins_id_t id = mix_ins_id_from_ins(*ins);
+  mix_word_t from;
+  
+  g_assert(id >= mix_STA && id <= mix_STZ);
+  switch (id) {
+  case mix_STA: from = get_rA_(vm); break;
+  case mix_STX: from = get_rX_(vm); break;
+  case mix_STJ: from = get_rJ_(vm); break;
+  case mix_STZ: from = MIX_WORD_ZERO; break;
+  default: from = get_rI_(vm, id - mix_ST1 + 1); break;
+  }
+  set_cell_(vm, addr,
+	    mix_word_store_field(ins->fspec, from,  get_cell_(vm, addr)));
+  inc_loc_(vm);
+  return TRUE;
+}
+
+static gboolean 
+jbs_handler_ (mix_vm_t *vm, const mix_ins_t *ins)
+{
+  g_assert (ins->opcode == mix_opJBUS);
+  g_return_val_if_fail (ins->fspec < BD_NO_, TRUE);
+  g_return_val_if_fail (get_dev_ (vm, ins->fspec) != NULL, TRUE);
+  if ( mix_device_busy (get_dev_ (vm, ins->fspec)) ) {
+      set_rJ_(vm, get_loc_ (vm));
+      set_loc_ (vm, get_M_ (vm, ins));
+  } else inc_loc_ (vm);
+  return TRUE;
+}
+
+static gboolean 
+ioc_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  mix_address_t addr;
+  mix_device_t *dev;
+  gboolean result;
+  
+  g_assert(ins->opcode == mix_opIOC);
+  addr = get_M_ (vm, ins);
+  g_return_val_if_fail (ins->fspec < BD_NO_, TRUE);
+  dev = get_dev_ (vm, ins->fspec);
+  g_return_val_if_fail (dev != NULL, TRUE);
+  result =
+    mix_device_ioc (dev, addr);
+    
+  inc_loc_(vm);
+  return result;
+}
+
+static gboolean 
+inp_handler_ (mix_vm_t *vm, const mix_ins_t *ins)
+{
+  mix_address_t addr;
+  mix_device_t *dev;
+  gboolean result;
+  
+  g_assert(ins->opcode == mix_opIN);
+  addr = get_M_ (vm, ins);
+  g_return_val_if_fail (ins->fspec < BD_NO_, TRUE);
+  g_return_val_if_fail (MEMOK_(addr), TRUE);
+  dev = get_dev_ (vm, ins->fspec);
+  g_return_val_if_fail ( dev != NULL, TRUE);
+  g_return_val_if_fail (MEM_CELLS_NO_ - addr > mix_device_block_size(dev),
+			TRUE);
+  result =
+    mix_device_read (dev, get_cell_ptr_ (vm, addr));
+    
+  inc_loc_(vm);
+  return result;
+}
+
+static gboolean 
+out_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  mix_address_t addr;
+  mix_device_t *dev;
+  gboolean result;
+  
+  g_assert(ins->opcode == mix_opOUT);
+  addr = get_M_ (vm, ins);
+  g_return_val_if_fail (ins->fspec < BD_NO_, TRUE);
+  g_return_val_if_fail (MEMOK_(addr), TRUE);
+  dev = get_dev_ (vm, ins->fspec);
+  g_return_val_if_fail ( dev != NULL, TRUE);
+  g_return_val_if_fail (MEM_CELLS_NO_ - addr > mix_device_block_size(dev),
+			TRUE);
+  result =
+    mix_device_write (dev, get_cell_ptr_ (vm, addr));
+  
+  inc_loc_(vm);
+  return result;
+}
+
+static gboolean 
+jrd_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  g_assert(ins->opcode == mix_opJRED);
+  g_return_val_if_fail (ins->fspec < BD_NO_, TRUE);
+  g_return_val_if_fail (get_dev_ (vm, ins->fspec) != NULL, TRUE);
+  if ( mix_device_busy (get_dev_ (vm, ins->fspec)) )
+    inc_loc_ (vm);
+  else {
+    set_rJ_(vm, get_loc_(vm));
+    set_loc_ (vm, get_M_ (vm, ins));
+  }
+  
+  return TRUE;
+}
+
+static gboolean
+jmp_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  gboolean jump = FALSE;
+  mix_address_t addr = get_M_(vm, ins);
+  mix_ins_id_t id = mix_ins_id_from_ins(*ins);
+  
+  g_assert(ins->opcode == mix_opJMP);
+  g_return_val_if_fail(MEMOK_(addr), FALSE);
+  switch ( id ) {
+  case mix_JMP:
+  case mix_JSJ:
+    jump = TRUE;
+    break;
+  case mix_JOV:
+    jump = get_over_(vm);
+    if (jump) set_over_(vm, FALSE);
+    break;
+  case mix_JNOV:
+    jump = !get_over_(vm);
+    set_over_(vm, FALSE);
+    break;
+  case mix_JL:
+    jump = ( get_cmp_(vm) == mix_LESS );
+    break;
+  case mix_JE:
+    jump = ( get_cmp_(vm) == mix_EQ );
+    break;
+  case mix_JG:
+    jump = ( get_cmp_(vm) == mix_GREAT );
+    break;
+  case mix_JGE:
+    jump = ( get_cmp_(vm) != mix_LESS );
+    break;
+  case mix_JNE:
+    jump = ( get_cmp_(vm) != mix_EQ );
+    break;
+  case mix_JLE:
+    jump = ( get_cmp_(vm) != mix_GREAT );
+    break;
+  default:
+    return FALSE;
+  }
+  
+  inc_loc_(vm);
+  if ( jump ) {
+    if ( id != mix_JSJ ) set_rJ_(vm, get_loc_(vm));
+    set_loc_(vm, addr);
+  }
+  return TRUE;
+}
+
+static gboolean
+jpx_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  gboolean jump = FALSE;
+  mix_address_t addr = get_M_(vm, ins);
+  mix_ins_id_t id = mix_ins_id_from_ins(*ins);
+  mix_word_t val;
+    
+  g_assert(ins->opcode >= mix_opJAx || ins->opcode <= mix_opJXx);
+  g_return_val_if_fail(MEMOK_(addr), FALSE);
+  
+  switch (ins->opcode) {
+  case mix_opJAx: val = get_rA_(vm); break;
+  case mix_opJXx: val = get_rX_(vm); break;
+  default: val = get_rI_(vm, ins->opcode - mix_opJAx);
+  }
+  
+  switch (id) {
+  case mix_JAN: case mix_JXN:
+  case mix_J1N: case mix_J2N: case mix_J3N:
+  case mix_J4N: case mix_J5N: case mix_J6N:
+    jump = mix_word_is_negative(val) && val != MIX_WORD_MINUS_ZERO;
+    break;
+  case mix_JAZ: case mix_JXZ:
+  case mix_J1Z: case mix_J2Z: case mix_J3Z:
+  case mix_J4Z: case mix_J5Z: case mix_J6Z:
+    jump = mix_word_magnitude(val) == MIX_WORD_ZERO;
+    break;
+  case mix_JAP: case mix_JXP:
+  case mix_J1P: case mix_J2P: case mix_J3P:
+  case mix_J4P: case mix_J5P: case mix_J6P:
+    jump = mix_word_is_positive(val) && val != MIX_WORD_ZERO;
+    break;
+  case mix_JANN: case mix_JXNN:
+  case mix_J1NN: case mix_J2NN: case mix_J3NN:
+  case mix_J4NN: case mix_J5NN: case mix_J6NN:
+    jump = mix_word_magnitude(val) == MIX_WORD_ZERO 
+      || mix_word_is_positive(val);
+    break;
+  case mix_JANZ: case mix_JXNZ:
+  case mix_J1NZ: case mix_J2NZ: case mix_J3NZ:
+  case mix_J4NZ: case mix_J5NZ: case mix_J6NZ:
+    jump = mix_word_magnitude(val) != MIX_WORD_ZERO;
+    break;
+  case mix_JANP: case mix_JXNP:
+  case mix_J1NP: case mix_J2NP: case mix_J3NP:
+  case mix_J4NP: case mix_J5NP: case mix_J6NP:
+    jump = mix_word_magnitude(val) == MIX_WORD_ZERO
+      || mix_word_is_negative(val);
+    break;
+  default:
+    return FALSE;
+  }
+  
+  inc_loc_(vm);
+  if ( jump ) {
+    set_rJ_(vm, get_loc_(vm));
+    set_loc_(vm, addr);
+  }
+  return TRUE;
+}
+
+static gboolean
+ina_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  mix_word_t val = mix_short_to_word_fast(get_M_(vm, ins));
+  mix_ins_id_t id = mix_ins_id_from_ins(*ins);
+  gint r;
+  
+  g_assert(id >= mix_INCA && id <= mix_ENNX);
+  
+  switch (ins->opcode) {
+  case mix_opINCA: r = A_; break;
+  case mix_opINCX: r = X_; break;
+  default: r = I1_ + ins->opcode - mix_opINC1;
+  }
+  
+  switch (id) {
+  case mix_ENTA: case mix_ENTX:
+    break;
+  case mix_ENT1: case mix_ENT2: case mix_ENT3: 
+  case mix_ENT4: case mix_ENT5: case mix_ENT6: 
+    val = mix_word_set_field(mix_fspec_new(1,3), MIX_WORD_ZERO, val);
+    break;
+  case mix_INCA: case mix_INCX:
+    if ( mix_word_add_and_carry(val, get_reg_(vm, r), NULL, &val) )
+      set_over_(vm, TRUE);
+    break;
+  case mix_INC1: case mix_INC2: case mix_INC3: 
+  case mix_INC4: case mix_INC5: case mix_INC6:
+    mix_word_add_and_carry(val, get_reg_(vm,r), NULL, &val);
+    val = mix_word_set_field(mix_fspec_new(1,3), MIX_WORD_ZERO, val);
+    break;
+  case mix_DECA: case mix_DECX:
+    if ( mix_word_add_and_carry(mix_word_negative(val), get_reg_(vm, r),
+				NULL, &val) )
+      set_over_(vm, TRUE);
+    break;
+  case mix_DEC1: case mix_DEC2: case mix_DEC3: 
+  case mix_DEC4: case mix_DEC5: case mix_DEC6: 
+    mix_word_add_and_carry(mix_word_negative(val), get_reg_(vm,r), NULL, &val);
+    val = mix_word_set_field(mix_fspec_new(1,3), MIX_WORD_ZERO, val);
+    break;
+  case mix_ENN1: case mix_ENN2: case mix_ENN3: 
+  case mix_ENN4: case mix_ENN5: case mix_ENN6: 
+    val = mix_word_set_field(mix_fspec_new(1,3), MIX_WORD_ZERO, val);
+    /* fallthrough */
+  case mix_ENNA: case mix_ENNX:
+    mix_word_reverse_sign(val);
+    break;
+  default:
+    return FALSE;
+  }
+  set_reg_(vm, r, val);
+  inc_loc_(vm);
+  return TRUE;
+}
+
+static gboolean
+cmp_handler_(mix_vm_t *vm, const mix_ins_t *ins)
+{
+  g_assert(ins->opcode >= mix_opCMPA && ins->opcode <= mix_opCMPX);
+
+  if ( ins->fspec == 0 ) { /* shortcut: +0 == -0 */
+    set_cmp_(vm, mix_EQ);
+  } else {
+    mix_word_t v = get_V_(vm, ins);
+    mix_word_t reg;
+    mix_cmpflag_t flag;
+    
+    switch (ins->opcode) {
+    case mix_opCMPA:
+      reg = get_rA_(vm);
+      break;
+    case mix_opCMPX:
+      reg = get_rX_(vm);
+      break;
+    default:
+      reg = get_rI_(vm, ins->opcode - mix_opCMPA);
+      break;
+    }
+    reg = mix_word_get_field(ins->fspec, reg);
+    mix_word_add_and_carry(reg, mix_word_negative(v), NULL, &reg);
+    if ( mix_word_magnitude(reg) == MIX_WORD_ZERO ) flag = mix_EQ;
+    else if ( mix_word_is_positive(reg) ) flag = mix_GREAT;
+    else flag = mix_LESS;
+    set_cmp_(vm, flag);
+  }
+  inc_loc_(vm);
+  return TRUE;
+}
+
+ins_handler_t_ ins_handlers_[MIX_BYTE_MAX + 1] = { 
+  nop_handler_, add_handler_, add_handler_, mul_handler_, div_handler_,
+  spc_handler_, sla_handler_, mov_handler_, lda_handler_, lda_handler_,
+  lda_handler_, lda_handler_, lda_handler_, lda_handler_, lda_handler_,
+  lda_handler_, lda_handler_, lda_handler_, lda_handler_, lda_handler_,
+  lda_handler_, lda_handler_, lda_handler_, lda_handler_, sta_handler_,
+  sta_handler_, sta_handler_, sta_handler_, sta_handler_, sta_handler_,
+  sta_handler_, sta_handler_, sta_handler_, sta_handler_, jbs_handler_,
+  ioc_handler_, inp_handler_, out_handler_, jrd_handler_, jmp_handler_,
+  jpx_handler_, jpx_handler_, jpx_handler_, jpx_handler_, jpx_handler_,
+  jpx_handler_, jpx_handler_, jpx_handler_, ina_handler_, ina_handler_,
+  ina_handler_, ina_handler_, ina_handler_, ina_handler_, ina_handler_,
+  ina_handler_, cmp_handler_, cmp_handler_, cmp_handler_, cmp_handler_,
+  cmp_handler_, cmp_handler_, cmp_handler_, cmp_handler_, 
+};
diff --git a/mixlib/xmix_vm.h b/mixlib/xmix_vm.h
new file mode 100644
index 0000000..ea2db61
--- /dev/null
+++ b/mixlib/xmix_vm.h
@@ -0,0 +1,111 @@
+/* ---------------------- xmix_vm.h :
+ * This file contains internal declarations used in the implementation
+ * of the mix_vm_t type.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef XMIX_VM_H
+#define XMIX_VM_H
+
+#include "mix_symbol_table.h"
+#include "mix_device.h"
+#include "mix_vm.h"
+
+/* The mix_vm_t type */
+enum {IREG_NO_ = 6, BD_NO_ = 21, MEM_CELLS_NO_ = MIX_VM_CELL_NO};
+struct mix_vm_t 
+{
+  mix_word_t reg[IREG_NO_+3];
+  mix_word_t cell[MEM_CELLS_NO_];
+  gboolean overflow;
+  mix_cmpflag_t cmpflag;
+  mix_short_t loc_count;
+  gboolean is_halted;
+  mix_device_t * devices[BD_NO_]; 
+  mix_address_t start_addr;	/* start address of loaded file */
+  GTree *line_table;		/* source line no -> address  */
+  gint8 bp[MEM_CELLS_NO_/8];	/* each bit signals a break point */
+  mix_symbol_table_t *symbol_table;
+};
+
+/* Macros for accessing/modifying the above structure.
+ * Warning: the arguments of these macros must not have side-effects.
+ */
+#define IOK_(idx) ( (idx) > 0 && (idx) < IREG_NO_+1 )
+#define MEMOK_(addr) ( mix_short_is_positive(addr) && (addr) < MEM_CELLS_NO_ )
+#define REGOK_(r) ( (r) >= 0 && (r) < IREG_NO_ + 3 )
+
+enum { A_ = 0, X_, J_, I1_, I2_, I3_, I4_, I5_, I6_ };
+
+#define get_reg_(vm, r) ((vm)->reg[r])
+#define get_rA_(vm)  get_reg_(vm, A_)
+#define get_rX_(vm)  get_reg_(vm, X_)
+#define get_rJ_(vm)  get_reg_(vm, J_)
+#define get_rI_(vm,idx) get_reg_(vm, I1_ + (idx) - 1)
+#define get_cell_(vm,addr) ( MEMOK_(addr) ? vm->cell[addr] : MIX_WORD_ZERO )
+#define get_cell_ptr_(vm,addr) ( MEMOK_(addr) ? (vm->cell) + addr : NULL )
+#define get_cmp_(vm) (vm->cmpflag)
+#define get_over_(vm) (vm->overflow)
+#define get_loc_(vm)  (vm->loc_count)
+
+#define set_reg_(vm,r,x)			\
+do {						\
+  if ( REGOK_(r) ) vm->reg[r] = (x);		\
+} while (FALSE)
+
+#define set_rA_(vm,x)  set_reg_(vm,A_,x)
+#define set_rX_(vm,x)  set_reg_(vm,X_,x)
+#define set_rJ_(vm,x)  set_reg_(vm,J_,(x)&MIX_SHORT_MAX)
+#define set_rI_(vm,idx,x)  set_reg_(vm,(idx) + I1_ - 1,x)
+
+#define set_cell_(vm,addr,x) 			\
+do {						\
+  if ( MEMOK_(addr) ) (vm)->cell[addr] = (x);	\
+} while (FALSE)
+
+#define set_cmp_(vm,x) (vm)->cmpflag = (x)
+#define set_over_(vm,x) (vm)->overflow = (x)
+#define set_loc_(vm,x)  (vm)->loc_count = (x)&MIX_SHORT_MAX
+
+#define inc_loc_(vm)   				\
+do {						\
+  vm->loc_count++;				\
+  vm->loc_count &= MIX_SHORT_MAX;		\
+} while(FALSE)
+
+#define is_halted_(vm) ((vm)->is_halted)
+#define halt_(vm,val) ((vm)->is_halted = (val))
+#define set_start_(vm,val) ((vm)->start_addr = (val))
+#define reset_loc_(vm) set_loc_ (vm, vm->start_addr)
+
+/* Breakpoints handling */
+#define bp_clear_all_(vm)	memset (vm->bp, 0, MEM_CELLS_NO_/8)
+#define bp_set_(vm,addr)	vm->bp[(addr)>>3] |= 1 << ((addr)&7)
+#define bp_clear_(vm,addr)	vm->bp[(addr)>>3] &= ~(1 << ((addr)&7))
+#define bp_is_set_(vm,addr)	vm->bp[(addr)>>3] & (1 << ((addr)&7))
+
+/* Instruction handlers */
+typedef gboolean (*ins_handler_t_)(mix_vm_t *,const mix_ins_t *);
+
+extern ins_handler_t_ ins_handlers_[MIX_BYTE_MAX + 1];
+
+
+#endif /* XMIX_VM_H */
+
diff --git a/mixutils/.cvsignore b/mixutils/.cvsignore
new file mode 100644
index 0000000..349354d
--- /dev/null
+++ b/mixutils/.cvsignore
@@ -0,0 +1,6 @@
+.deps
+Makefile
+Makefile.in
+mixasm
+mixcmp
+mixvm
diff --git a/mixutils/Makefile.am b/mixutils/Makefile.am
new file mode 100644
index 0000000..710cc51
--- /dev/null
+++ b/mixutils/Makefile.am
@@ -0,0 +1,18 @@
+## Process this file with automake to produce Makefile.in
+
+# Copyright (C) 2000 jose antonio ortega ruiz <jaortega@retemail.es>
+#  
+# This file is free software; as a special exception the author gives
+# unlimited permission to copy and/or distribute it, with or without 
+# modifications, as long as this notice is preserved.
+# 
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+INCLUDES = -I$(includedir) 
+LDADD = $(top_builddir)/mixlib/libmix.a 
+
+bin_PROGRAMS = mixasm mixvm
+mixasm_SOURCES = mixasm.c mixasm_comp.h mixasm_comp.c
+mixvm_SOURCES = mixvm.c mixvm_loop.c mixvm_command.h mixvm_command.c
diff --git a/mixutils/mixasm.c b/mixutils/mixasm.c
new file mode 100644
index 0000000..935e5d1
--- /dev/null
+++ b/mixutils/mixasm.c
@@ -0,0 +1,126 @@
+/* -*-c-*- -------------- mixasm.c:
+ * Main function of mixasm, the mix assembler
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+#include <mixlib/mix.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <getopt.h>
+
+#include "mixasm_comp.h"
+
+enum {
+  VER_OPT = 'v',
+  HELP_OPT = 'h',
+  USAGE_OPT = 'u',
+  OUT_OPT =  'o',
+  LIST_OPT = 'l',
+  DEBUG_OPT = 'g'
+};
+
+
+static struct option long_options_[] =
+{
+  {"version", no_argument, 0, VER_OPT},
+  {"help", no_argument, 0, HELP_OPT},
+  {"usage", no_argument, 0, USAGE_OPT},
+  {"output", required_argument, 0, OUT_OPT},
+  {"list", optional_argument, 0, VER_OPT},
+  {"debug", no_argument, 0, DEBUG_OPT},
+  {0, 0, 0, 0}
+};
+
+static const gchar *USAGE_ = 
+N_("Usage: %s [-vhulg] [-o OUTPUT_FILE] [--version] [--help]\n"
+   "\t[--usage] [--debug] [--output=OUTPUT_FILE] [--list[=LIST_FILE]] file\n");
+
+     
+int
+main (int argc, char **argv)
+{
+  int c;
+  const char *prog_name = argv[0];
+  const char *src = NULL, *out = NULL, *list = NULL;
+  gboolean use_list = FALSE, debug = FALSE;
+
+  setlocale (LC_ALL, "");
+  bindtextdomain (PACKAGE, LOCALEDIR);
+  textdomain (PACKAGE);
+
+  while (1)
+    {
+      c = getopt_long (argc, argv, "vhuo:lg", long_options_, (int*)0);
+     
+      /* Detect the end of the options. */
+      if (c == -1)
+	break;
+     
+      switch (c)
+	{
+	case HELP_OPT: case USAGE_OPT:
+	  fprintf (stderr, _(USAGE_), prog_name);
+	  return EXIT_SUCCESS;
+     	case VER_OPT:
+	  fprintf (stderr, _("%s %s, MIX compiler.\n"), prog_name, VERSION);
+	  fprintf (stderr, MIX_GPL_LICENSE);
+	  return EXIT_SUCCESS;
+	case OUT_OPT:
+	  out = optarg;
+	  break;
+     	case LIST_OPT:
+	  use_list = TRUE;
+	  list = optarg;
+	  break;
+	case DEBUG_OPT:
+	  debug = TRUE;
+	  break;
+     	case '?':
+	  /* getopt already handles the output of a warning message */
+	  fprintf (stderr, _("(Try: %s -h)\n"), prog_name);
+	  return EXIT_FAILURE;
+	default:
+	  g_assert_not_reached ();
+	}
+    }
+   
+  if ( optind == argc )
+    {
+      fprintf (stderr, _("*** Error: Missing source file.\n"));
+      return EXIT_FAILURE;
+    }
+  if ( optind < argc-1 )
+    {
+      fprintf (stderr, _("*** Error: Too many input files.\n"));
+      return EXIT_FAILURE;
+    }
+  src = argv[optind];
+
+  
+  mix_init_lib ();
+  
+  c = mix_asm_compile (src, out, use_list, list, debug);
+
+  mix_release_lib ();
+  
+  return c;
+  
+}
+
diff --git a/mixutils/mixasm_comp.c b/mixutils/mixasm_comp.c
new file mode 100644
index 0000000..3a31363
--- /dev/null
+++ b/mixutils/mixasm_comp.c
@@ -0,0 +1,72 @@
+/* -*-c-*- -------------- mixasm_comp.c :
+ * Implementation of the functions declared in mixasm_comp.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+#include <mixlib/mix.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <mixlib/mix_parser.h>
+#include "mixasm_comp.h"
+
+int
+mix_asm_compile(const gchar *src, const gchar *out, gboolean use_list,
+		const gchar *list, gboolean debug)
+{
+  int result = EXIT_SUCCESS;
+  mix_parser_t *parser;
+  mix_parser_err_t error;
+  
+  if ( (parser = mix_parser_new(src)) == NULL )
+    {
+      fprintf(stderr, _("*** Unable to open source file %s\n"), src);
+      return EXIT_FAILURE;
+    }
+  if ( mix_parser_compile(parser) == MIX_PERR_OK )
+    {
+      guint k;
+      if ( ( k = mix_parser_warning_count(parser) ) != 0 )
+	fprintf(stderr, _("(%d warning(s))\n"), k);
+      if ( (error = mix_parser_write_code(parser, out, debug)) != MIX_PERR_OK )
+	{
+	  fprintf(stderr, _("*** Error writing output code file: %s\n"),
+		  mix_parser_err_string(error));
+	  result = EXIT_FAILURE;
+	}
+      else if ( use_list 
+		&& (error = mix_parser_write_listing(parser, list)) != 
+		MIX_PERR_OK)
+	{
+	  fprintf(stderr, _("*** Error writing listing file: %s\n"),
+		  mix_parser_err_string(error));
+	  result = EXIT_FAILURE;
+	}
+    }
+  else
+    {
+      fprintf(stderr, _("(%d warning(s), %d error(s))\n"), 
+	      mix_parser_warning_count(parser), mix_parser_err_count(parser));
+      result = EXIT_FAILURE;
+    }
+  
+  mix_parser_delete(parser);
+  return result;
+}
+
+
diff --git a/mixutils/mixasm_comp.h b/mixutils/mixasm_comp.h
new file mode 100644
index 0000000..74c0474
--- /dev/null
+++ b/mixutils/mixasm_comp.h
@@ -0,0 +1,35 @@
+/* -*-c-*- ---------------- mixasm_comp.h :
+ * Declarations of functions used to compile mix source files.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIXASM_COMP_H
+#define MIXASM_COMP_H
+
+#include <glib.h>
+
+extern int
+mix_asm_compile(const gchar *src, const gchar *out, gboolean use_list,
+		const gchar *list, gboolean debug);
+
+
+
+#endif /* MIXASM_COMP_H */
+
diff --git a/mixutils/mixvm.c b/mixutils/mixvm.c
new file mode 100644
index 0000000..207eca8
--- /dev/null
+++ b/mixutils/mixvm.c
@@ -0,0 +1,148 @@
+/* -*-c-*- -------------- mixvm.c :
+ * Main function for mixvm, the mix vm simulator
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+
+#include <mixlib/mix.h>
+#include <mixlib/mix_vm.h>
+#include <mixlib/mix_vm_dump.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <getopt.h>
+
+extern void
+mix_vmloop (const gchar *code_file);
+
+static void
+mix_vmrun (const gchar *code_file, gboolean dump);
+
+enum {
+  VER_OPT = 'v',
+  HELP_OPT = 'h',
+  USAGE_OPT = 'u',
+  RUN_OPT = 'r',
+  DUMP_OPT = 'd'
+};
+
+static const char *options_ = "vhurd";
+
+static struct option long_options_[] =
+{
+  {"version", no_argument, 0, VER_OPT},
+  {"help", no_argument, 0, HELP_OPT},
+  {"usage", no_argument, 0, USAGE_OPT},
+  {"run", required_argument, 0, RUN_OPT},
+  {"dump", no_argument, 0, DUMP_OPT},
+  {0, 0, 0, 0}
+};
+
+static const gchar *USAGE_ = 
+N_("Usage: %s [-vhurd] [--version] [--help] [--usage] [--run] [--dump] [MIX_FILE]\n");
+
+     
+int
+main (int argc, char **argv)
+{
+  int c;
+  const char *prog_name = argv[0];
+  const char *in = NULL;
+  gboolean run = FALSE;
+  gboolean dump = FALSE;
+      
+  setlocale (LC_ALL, "");
+  bindtextdomain (PACKAGE, LOCALEDIR);
+  textdomain (PACKAGE);
+
+  while (1)
+    {
+      c = getopt_long (argc, argv, options_, long_options_, (int*)0);
+     
+      /* Detect the end of the options. */
+      if (c == -1)
+	break;
+     
+      switch (c)
+	{
+	case HELP_OPT: case USAGE_OPT:
+	  fprintf (stderr, _(USAGE_), prog_name);
+	  return EXIT_SUCCESS;
+     	case VER_OPT:
+	  fprintf (stderr, _("%s %s, MIX Virtual Machine.\n"), 
+		   prog_name, VERSION);
+	  fprintf (stderr, MIX_GPL_LICENSE);
+	  return EXIT_SUCCESS;
+	case RUN_OPT:
+	  in = optarg;
+	  run = TRUE;
+	  break;
+	case DUMP_OPT:
+	  dump = TRUE;
+	  break;
+     	case '?':
+	  /* getopt already handles the output of a warning message */
+	  fprintf (stderr, _("(Try: %s -h)\n"), prog_name);
+	  return EXIT_FAILURE;
+	default:
+	  g_assert_not_reached ();
+	}
+    }
+   
+  if ( optind < argc-1 )
+    {
+      fprintf (stderr, _("*** Error: Too many input files.\n"));
+      return EXIT_FAILURE;
+    }
+  
+  if (!in)  in = argv[optind];
+  
+  mix_init_lib ();
+  
+  if (run) mix_vmrun(in, dump);
+  else mix_vmloop (in);
+
+  mix_release_lib ();
+  
+  return EXIT_SUCCESS;
+  
+}
+
+
+static void
+mix_vmrun (const gchar *code_file, gboolean dump) 
+{
+  mix_vm_t *vm = mix_vm_new ();
+  if (!mix_vm_load_file (vm, code_file)) {
+    fprintf (stderr, _("Error loading %s file\n"), code_file);
+    return;
+  }
+  mix_vm_run (vm);
+  if (dump) {
+    mix_dump_context_t *dc = mix_dump_context_new (MIX_DUMP_DEF_CHANNEL,
+						   0, 0,
+						   MIX_DUMP_ALL_NOMEM);
+    mix_vm_dump (vm, dc);
+    mix_dump_context_delete (dc);
+  }
+  mix_vm_delete (vm);
+}
+
+  
diff --git a/mixutils/mixvm_command.c b/mixutils/mixvm_command.c
new file mode 100644
index 0000000..e03dcfd
--- /dev/null
+++ b/mixutils/mixvm_command.c
@@ -0,0 +1,867 @@
+/* -*-c-*- -------------- mixvm_command.c :
+ * Implementation of the functions declared in mixvm_command.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#include <mixlib/mix.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <errno.h>
+#include <readline/readline.h>
+#include <readline/history.h>
+
+#include <mixlib/mix_vm.h>
+#include <mixlib/mix_vm_dump.h>
+#include "mixvm_command.h"
+
+/* The names of functions that actually do the manipulation. */
+#define DEC_FUN(name) \
+static int cmd_##name (char *arg)
+
+DEC_FUN (help_);
+DEC_FUN (shell_);
+DEC_FUN (load_);
+DEC_FUN (run_);
+DEC_FUN (next_);
+DEC_FUN (pc_);
+DEC_FUN (psym_);
+DEC_FUN (preg_);
+DEC_FUN (pflags_);
+DEC_FUN (pall_);
+DEC_FUN (pmem_);
+DEC_FUN (sreg_);
+DEC_FUN (scmp_);
+DEC_FUN (sover_);
+DEC_FUN (smem_);
+DEC_FUN (sbp_);
+DEC_FUN (sbpa_);
+DEC_FUN (cbp_);
+DEC_FUN (cbpa_);
+DEC_FUN (cabp_);
+DEC_FUN (compile_);
+DEC_FUN (edit_);
+DEC_FUN (quit_);
+
+/* A structure which contains information on the commands this program
+   can understand. */
+typedef struct {
+  const char *name;		/* User printable name of the function. */
+  Function *func;		/* Function to call to do the job. */
+  const char *doc;		/* Documentation for this function.  */
+  const char *usage;		/* Usage */
+} COMMAND;
+     
+COMMAND commands[] = {
+  { "help", cmd_help_, N_("Display this text"), "help [COMMAND]" },
+  { "?", cmd_help_, N_("Synonym for `help'"), "? [COMMAND]" },
+  { "!", cmd_shell_, N_("Execute shell command"), "! COMMAND" },
+  { "load", cmd_load_, N_("Load a MIX code file"), "load FILENAME" },
+  { "run", cmd_run_, N_("Run loaded or given MIX code file"), 
+    "run [FILENAME]" },
+  { "next", cmd_next_, N_("Execute next instruction(s)"), 
+    "next [NO_OF_INS]"},
+  { "pc", cmd_pc_, N_("Print program counter value"), "pc" },
+  { "psym", cmd_psym_, N_("Print symbol value"), "psym [SYMBOLNAME]" },
+  { "preg", cmd_preg_, N_("Print register value"), 
+    "preg [A | X | J | I[1-6]]" },
+  { "pflags", cmd_pflags_, N_("Print comparison and overflow flags"), 
+    "pflags" },
+  { "pall", cmd_pall_, N_("Print all registers and flags"), "pall" },
+  { "pmem", cmd_pmem_, N_("Print memory contents in address range"), 
+    "pmem FROM[-TO]" },
+  { "sreg", cmd_sreg_, N_("Set register value"), 
+    "preg A | X | J | I[1-6] VALUE" },
+  { "scmp", cmd_scmp_, N_("Set comparison flag value"), "scmp L | E | G" },
+  { "sover", cmd_sover_, N_("Set overflow flag value"), "sover T | F" },
+  { "smem", cmd_smem_, N_("Set memory contents in given address"), 
+    "smem ADDRESS VALUE" },
+  { "sbp", cmd_sbp_, N_("Set break point at given line"), "sbp LINENO" },
+  { "cbp", cmd_cbp_, N_("Clear break point at given line"), "cbp LINENO" },
+  { "sbpa", cmd_sbpa_, N_("Set break point at given address"),
+    "sbpa ADDRESS" },
+  { "cbpa", cmd_cbpa_, N_("Clear break point at given address"),
+    "cbpa ADDRESS" },
+  { "cabp", cmd_cabp_, N_("Clear all breakpoints"), "cabp" },
+  { "compile", cmd_compile_, N_("Compile a source file"), "compile FILENAME"},
+  { "edit", cmd_edit_, N_("Edit a source file"), "edit FILENAME"},
+  { "quit", cmd_quit_, N_("Quit the program"), "quit" },
+  { (char *)NULL, (Function *)NULL, (char *)NULL }
+};
+
+
+/* readline functions */
+static char *
+mixvm_cmd_generator_ (char *text, int state);
+
+
+/* Attempt to complete on the contents of TEXT.  START and END bound the
+   region of rl_line_buffer that contains the word to complete.  TEXT is
+   the word to complete.  We can use the entire contents of rl_line_buffer
+   in case we want to do some simple parsing.  Return the array of matches,
+   or NULL if there aren't any. */
+static char **
+mixvm_cmd_completion_ (char *text, int start, int end)
+{
+  char **matches;
+     
+  matches = (char **)NULL;
+     
+  /* If this word is at the start of the line, then it is a command
+     to complete.  Otherwise it is the name of a file in the current
+     directory. */
+  if (start == 0)
+    matches = completion_matches (text, mixvm_cmd_generator_);
+  
+  return (matches);
+}
+     
+/* Generator function for command completion.  STATE lets us know whether
+   to start from scratch; without any state (i.e. STATE == 0), then we
+   start at the top of the list. */
+static char *
+mixvm_cmd_generator_ (char *text, int state)
+{
+  static int list_index, len;
+  const char *name;
+     
+  /* If this is a new word to complete, initialize now.  This includes
+     saving the length of TEXT for efficiency, and initializing the index
+     variable to 0. */
+  if (!state)
+    {
+      list_index = 0;
+      len = strlen (text);
+    }
+     
+  /* Return the next name which partially matches from the command list. */
+  while ( (name = commands[list_index].name) != NULL)
+    {
+      list_index++;
+     
+      if (strncmp (name, text, len) == 0)
+	return (g_strdup (name));
+    }
+     
+  /* If no names matched, then return NULL. */
+  return ((char *)NULL);
+}
+
+
+/* command functions */
+static COMMAND *
+find_command_ (const char *name)
+{
+  int i;
+     
+  for (i = 0; commands[i].name; i++)
+    if (strcmp (name, commands[i].name) == 0)
+      return (&commands[i]);
+     
+  return ((COMMAND *)NULL);
+}
+
+
+/* the virtual machine and dump context */
+static mix_vm_t *vm_ = NULL;
+static mix_dump_context_t *dc_ = NULL;
+
+static int
+cmd_help_ (char *arg)
+{
+  static const int NO_OF_COLS = 6;
+  
+  int i;
+  int printed = 0;
+     
+  for (i = 0; commands[i].name; i++)
+    {
+      if (!*arg || (strcmp (arg, commands[i].name) == 0))
+	{
+	  printf (_("%s\t\t%s. Usage: %s\n"), commands[i].name, 
+		  _(commands[i].doc), commands[i].usage);
+	  printed++;
+	}
+    }
+     
+  if (!printed)
+    {
+      printf (_("No commands match `%s'.  Possibilities are:\n"), arg);
+     
+      for (i = 0; commands[i].name; i++)
+	{
+	  if (printed == NO_OF_COLS)
+	    {
+	      printed = 0;
+	      printf ("\n");
+	    }
+     
+	  printf ("%s\t", commands[i].name);
+	  printed++;
+	}
+     
+      if (printed)
+	printf ("\n");
+    }
+  return TRUE;
+}
+
+static int
+cmd_load_ (char *arg)
+{
+  errno = 0;
+  if (arg == NULL || *arg == '\0')
+    fputs (_("Missing file name\n"), stderr);
+  else if (!mix_vm_load_file (vm_, arg) )
+    {
+      fprintf (stderr, _("Cannot load %s: "), arg);
+      if ( errno == 0 )
+	fputs (_("Wrong file format\n"), stderr);
+      else
+	perror (NULL);
+      return TRUE + 1;
+    }
+  fprintf (stderr, _("Program loaded. Start address: %d\n"),
+	   mix_vm_get_prog_count (vm_));
+  
+  return TRUE;
+}
+
+static int
+cmd_run_ (char *arg)
+{
+  if (arg != NULL && *arg != '\0' && cmd_load_ (arg) != TRUE) 
+      return TRUE;
+  puts (_("Running ..."));
+  switch (mix_vm_run (vm_))
+    {
+    case MIX_VM_HALT:
+      puts (_("... done"));
+      break;
+    case MIX_VM_BREAK:
+      {
+	gulong line = mix_vm_get_break_lineno (vm_);
+	if (line != 0)
+	  printf (_("... stopped: breakpoint at line %ld (address %d)\n"), 
+		  line, mix_vm_get_prog_count (vm_));
+	else
+	  printf (_("... stopped: breakpoint at address %d\n"),
+		  mix_vm_get_prog_count (vm_));
+      }
+      break;
+    case MIX_VM_ERROR:
+      puts (_("... error executing loaded file"));
+      break;
+    default:
+      g_assert_not_reached ();
+      break;
+    }
+  return TRUE;
+}
+
+static int
+cmd_next_ (char *arg)
+{
+  int ins_no = 1;
+  if ( strlen (arg) != 0 )
+    {
+      int k = 0;
+      while (isdigit (arg[k]))
+	k++;
+      if (arg[k] != '\0')
+	{
+	  fprintf (stderr, _("Invalid argument: %s\n"), arg);
+	  return cmd_help_ ("next");
+	}
+      ins_no = atoi (arg);
+    }
+
+  while ( ins_no-- > 0 )
+    {
+      int k = mix_vm_exec_next (vm_);
+      if (k == MIX_VM_HALT)
+	{
+	  fprintf (stderr, _("End of program reached at address %d\n"),
+		   mix_vm_get_prog_count (vm_));
+	  break;
+	}
+      else if (k == MIX_VM_ERROR)
+	{
+	  fprintf (stderr, _("Error at address %d\n"),
+		   mix_vm_get_prog_count (vm_));
+	  break;
+	}
+    }
+
+  return TRUE;
+}
+
+static int
+cmd_quit_ (char *arg)
+{
+  puts ("Quitting ...");
+  if ( vm_ ) mix_vm_delete (vm_);
+  if ( dc_ ) mix_dump_context_delete (dc_);
+  return FALSE;
+}
+
+static int
+cmd_pc_ (char *arg)
+{
+  printf ("Current address: %d\n", mix_vm_get_prog_count (vm_));
+  return TRUE;
+}
+
+static int
+cmd_psym_ (char *arg)
+{
+  const mix_symbol_table_t *table = mix_vm_get_symbol_table (vm_);
+  if ( table == NULL )
+    fputs (_("Symbol table not available\n"), stderr);
+  else if (arg != NULL && *arg != '\0')
+    {
+      if ( mix_symbol_table_is_defined (table, arg) )
+	{
+	  mix_word_print (mix_symbol_table_value (table, arg), NULL);
+	  puts ("\n");
+	}
+      else
+	printf (_("%s: symbol not defined\n"), arg);
+    }
+  else
+    mix_symbol_table_print (table, MIX_SYM_ROWS, stdout);
+      
+  return TRUE;
+}
+
+static int
+cmd_preg_ (char *arg)
+{
+  mix_dump_context_set_opt (dc_, MIX_DUMP_NONE);
+  if ( strlen (arg) == 0 )
+    mix_dump_context_add_opt (dc_, MIX_DUMP_rALL);
+  else switch (*arg)
+    {
+    case 'A':
+      mix_dump_context_add_opt (dc_, MIX_DUMP_rA);
+      break;
+    case 'X':
+      mix_dump_context_add_opt (dc_, MIX_DUMP_rX);
+      break;
+    case 'J':
+      mix_dump_context_add_opt (dc_, MIX_DUMP_rJ);
+      break;
+    case 'I':
+      {
+	if ( strlen (arg) == 1 )
+	  mix_dump_context_add_opt (dc_, MIX_DUMP_rIa);
+	else
+	  {
+	    static gint32 opt[] = { MIX_DUMP_rI1, MIX_DUMP_rI2,
+				    MIX_DUMP_rI3, MIX_DUMP_rI4,
+				    MIX_DUMP_rI5, MIX_DUMP_rI6 
+	    };
+	    int i = arg[1] - '1';
+	    if ( i < 0 || i > 5 )
+	      {
+		fprintf (stderr, _("Invalid I index: %d"), i);
+		return TRUE;
+	      }
+	    mix_dump_context_add_opt (dc_, opt[i]);
+	  }
+      }
+      break;
+    default:
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return TRUE;
+    }
+  mix_vm_dump (vm_, dc_);
+  return TRUE;
+}
+
+static int
+cmd_pflags_ (char *arg)
+{
+  mix_dump_context_set_opt (dc_, MIX_DUMP_CMP | MIX_DUMP_OVER);
+  mix_vm_dump (vm_, dc_);
+  return TRUE;
+}
+
+static int
+cmd_pall_ (char *arg)
+{
+  mix_dump_context_set_opt (dc_, MIX_DUMP_ALL_NOMEM);
+  mix_vm_dump (vm_, dc_);
+  return TRUE;
+}
+
+static int
+cmd_pmem_ (char *arg)
+{
+  glong begin = MIX_SHORT_ZERO, end = MIX_SHORT_ZERO;
+  int i = 0;
+  gboolean error = FALSE;
+  
+  if ( strlen (arg) == 0 )
+    {
+      fputs (_("Missing memory address\n"), stderr);
+      return TRUE;
+    }
+  while (isdigit (arg[i]))
+    i++;
+  while (isspace (arg[i]))
+    i++;
+  if (arg[i] == '\0')
+      begin = end = atol (arg);
+  else if (arg[i] == '-')
+    {
+      arg[i++] = '\0';
+      begin = atol (arg);
+      arg = arg + i;
+      i = 0;
+      while (isdigit (arg[i]))
+	i++;
+      while (isspace (arg[i]))
+	i++;
+      if (arg[i] != '\0') 
+	error = TRUE;
+      else 
+	end = atol (arg);
+    }
+  else
+    error = TRUE;
+  
+  if (error)
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_("pmem");
+    }
+  if ( end < begin || end > MIX_VM_CELL_NO - 1 )
+    {
+      fprintf (stderr, _("Invalid range: %ld-%ld\n"), begin, end);
+      return TRUE;
+    }
+
+  mix_dump_context_set_opt (dc_, MIX_DUMP_CELLS);
+  mix_dump_context_range (dc_, mix_short_new (begin), mix_short_new (end + 1));
+  mix_vm_dump (vm_, dc_);
+  
+  return TRUE;
+}
+
+static int
+cmd_sreg_ (char *arg)
+{
+  int i = 0;
+  char reg = arg[0];
+  gboolean ok = TRUE;
+  long value;
+  
+  i = (reg == 'I') ? 2 : 1;
+  ok = strlen (arg) > 2 && isspace (arg[i]);
+  if (ok)
+    {
+      while (isspace (arg[i])) i++;
+      ok = isdigit (arg[i]) || arg[i] == '+' || arg[i] == '-';
+      if (ok)
+	{
+	  value = atol (arg + i);
+	  if (arg[i] == '+' || arg[i] == '-') i++;
+	  while (isdigit (arg[i])) i++;
+	  ok = (arg[i] == '\0');
+	  if (ok)
+	    switch (reg)
+	      {
+	      case 'A':
+		mix_vm_set_rA (vm_, mix_word_new (value));
+		break;
+	      case 'X':
+		mix_vm_set_rX (vm_, mix_word_new (value));
+		break;
+	      case 'J':
+		if ( value >= 0 )
+		  mix_vm_set_rJ (vm_, mix_short_new (value));
+		else
+		  ok = FALSE;
+		break;
+	      case 'I':
+		{
+		  guint k = arg[1] - '0';
+		  if ( k < 7 ) 
+		    mix_vm_set_rI (vm_, k, mix_short_new (value));
+		  else
+		    ok = FALSE;
+		}
+		break;
+	      default:
+		ok = FALSE;
+	      }
+	}
+    }
+  if (!ok)
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      cmd_help_ ("sreg");
+    }
+    
+  return TRUE;
+}
+
+static int
+cmd_scmp_ (char *arg)
+{
+  gboolean ok = (strlen (arg) == 1);
+  if (ok) switch (arg[0])
+    {
+    case 'L':
+      mix_vm_set_cmpflag (vm_, mix_LESS);
+      break;
+    case 'E':
+      mix_vm_set_cmpflag (vm_, mix_EQ);
+      break;
+    case 'G':
+      mix_vm_set_cmpflag (vm_, mix_GREAT);
+      break;
+    default:
+      ok = FALSE;
+    }
+  if (!ok)
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      cmd_help_ ("scmp");
+    }
+  
+  return TRUE;
+}
+
+static int
+cmd_sover_ (char *arg)
+{
+  gboolean ok = (strlen (arg) == 1);
+  if (ok) switch (arg[0])
+    {
+    case 'T':
+      mix_vm_set_overflow (vm_, TRUE);
+      break;
+    case 'F':
+      mix_vm_set_overflow (vm_, FALSE);
+      break;
+    default:
+      ok = FALSE;
+    }
+  if (!ok)
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      cmd_help_ ("sover");
+    }
+  
+  return TRUE;
+}
+
+static int
+cmd_smem_ (char *arg)
+{
+  gboolean ok = (strlen (arg) > 2 && isdigit (arg[0]));
+  gulong addr;
+  glong value;
+  int k = 0;
+  
+  if (ok)
+    {
+      while (isdigit (arg[k])) k++;
+      ok = isspace (arg[k]);
+      if (ok)
+	{
+	  arg[k++] = '\0';
+	  addr = atol (arg);
+	  ok = addr < MIX_VM_CELL_NO;
+	}
+      if (ok)
+	{
+	  while (isspace (arg[k])) k++;
+	  value = atol (arg + k);
+	  if ( arg[k] == '+' || arg[k] == '-' ) k++;
+	  while (isdigit (arg[k])) k++;
+	  ok = arg[k] == '\0';
+	}
+    }
+
+  if (ok)
+    mix_vm_set_addr_contents (vm_, mix_short_new (addr), mix_word_new (value));
+  else
+    {
+      fprintf (stderr, "Invalid argument: %s\n", arg);
+      cmd_help_ ("smem");
+    }
+  
+  return TRUE;
+}
+
+static int
+cmd_sbp_ (char *arg)
+{
+  glong lineno;
+  glong k = 0;
+  while (isdigit (arg[k])) k++;
+  if (arg[k] != '\0')
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_ ("sbp");
+    }
+  lineno = atol (arg);
+  switch (k = mix_vm_set_breakpoint (vm_, lineno))
+    {
+    case MIX_VM_BP_INV_LINE:
+      fprintf (stderr, _("Line number %ld too high\n"), lineno);
+      break;
+    case MIX_VM_BP_ERROR:
+      fputs (_("Could not set breakpoint. Internal error\n"), stderr);
+      break;
+    case MIX_VM_BP_NDEBUG:
+      fputs (_("Could not set breakpoint. No debug info available\n"), stderr);
+      break;
+    default:
+      fprintf (stderr, _("Breakpoint set at line %ld\n"), k);
+      break;
+    }
+  return TRUE;
+}
+
+static int
+cmd_sbpa_ (char *arg)
+{
+  glong address;
+  glong k = 0;
+  while (isdigit (arg[k])) k++;
+  if (arg[k] != '\0')
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_ ("sbpa");
+    }
+  address = atol (arg);
+  switch (mix_vm_set_breakpoint_address (vm_, address))
+    {
+    case MIX_VM_BP_INV_ADDRESS:
+      fprintf (stderr, _("Invalid address %ld\n"), address);
+      break;
+    case MIX_VM_BP_ERROR:
+      fputs (_("Could not set breakpoint. Internal error\n"), stderr);
+      break;
+    default:
+      fprintf (stderr, _("Breakpoint set at address %ld\n"), address);
+      break;
+    }
+  return TRUE;
+}
+
+static int
+cmd_cbp_ (char *arg)
+{
+  glong lineno;
+  int k = 0;
+  while (isdigit (arg[k])) k++;
+  if (arg[k] != '\0')
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_ ("cbp");
+    }
+  lineno = atol (arg);
+  switch (mix_vm_clear_breakpoint (vm_, lineno))
+    {
+    case MIX_VM_BP_INV_LINE:
+      fprintf (stderr, _("No breakpoint set at line %ld\n"), lineno);
+      break;
+    case MIX_VM_BP_ERROR:
+      fputs (_("Could not set breakpoint. Internal error\n"), stderr);
+      break;
+    case MIX_VM_BP_NDEBUG:
+      fputs (_("No debug info available\n"), stderr);
+      break;
+    case MIX_VM_BP_OK:
+      fprintf (stderr, _("Breakpoint cleared at line %ld\n"), lineno);
+      break;
+    default:
+      g_assert_not_reached ();
+      break;
+    }
+  return TRUE;
+}
+
+static int
+cmd_cbpa_ (char *arg)
+{
+  glong address;
+  glong k = 0;
+  while (isdigit (arg[k])) k++;
+  if (arg[k] != '\0')
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_ ("cbpa");
+    }
+  address = atol (arg);
+  switch (mix_vm_clear_breakpoint_address (vm_, address))
+    {
+    case MIX_VM_BP_INV_ADDRESS:
+      fprintf (stderr, _("Invalid address %ld\n"), address);
+      break;
+    case MIX_VM_BP_ERROR:
+      fputs (_("Could not clear breakpoint. Internal error\n"), stderr);
+      break;
+    default:
+      fprintf (stderr, _("Breakpoint cleared at address %ld\n"), address);
+      break;
+    }
+  return TRUE;
+}
+
+
+static int
+cmd_cabp_ (char *arg)
+{
+  if (strlen (arg) != 0)
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_ ("cabp");
+    }
+  mix_vm_clear_all_breakpoints (vm_);
+  return TRUE;
+}
+
+static int 
+cmd_shell_ (char *arg)
+{
+  system (arg);
+  return TRUE;
+}
+
+static int
+cmd_compile_ (char *arg)
+{
+  gchar *line;
+  
+  if ( strlen (arg) == 0 )
+    return cmd_help_ ("compile");
+  
+  line = g_strconcat ("mixasm -g ", arg, NULL);
+  if ( system (line) == EXIT_SUCCESS )
+    fputs (_("Successful compilation\n"), stderr);
+  g_free (line);
+  
+  return TRUE;
+}
+
+static int
+cmd_edit_ (char *arg)
+{
+  static const gchar * envars[] = { "MDK_EDITOR", "X_EDITOR", "EDITOR",
+				    "VISUAL" 
+  };
+  static const guint s = sizeof (envars) / sizeof (envars[0]);
+  static const gchar *editor = NULL;
+  
+  if ( strlen (arg) == 0 )
+    return cmd_help_ ("edit");
+  
+  if (!editor)
+    {
+      int k;
+      for (k = 0; k < s; k++)
+	if ( (editor = getenv (envars[k])) != NULL ) break;
+    }
+  if (!editor)
+    {
+      int k;
+      fputs ("Cannot find editor (", stderr);
+      for (k = 0; k < s; k++)
+	fprintf (stderr, "%s ", envars[k]);
+      fputs ("undefined)\n", stderr);
+    }
+  else
+    {
+      gchar *line = g_strconcat (editor, " ", arg, NULL);
+      system (line);
+      g_free (line);
+    }
+  
+  return TRUE;
+}
+
+
+/* external interface */
+void
+mixvm_cmd_init (char *arg)
+{
+  /* Tell the completer that we want a crack first. */
+  rl_attempted_completion_function = (CPPFunction *)mixvm_cmd_completion_;
+  /* initialise the vm */
+  vm_ = mix_vm_new ();
+  dc_ = mix_dump_context_new (MIX_DUMP_DEF_CHANNEL, 
+			      MIX_SHORT_ZERO, MIX_SHORT_ZERO,
+			      MIX_DUMP_ALL);
+  if ( vm_ == NULL || dc_ == NULL )
+    g_error (_("Failed initialisation (no memory resources)"));
+  if (arg)
+    cmd_load_ (arg);
+}
+
+gboolean
+mixvm_cmd_exec (char *line)
+{
+  int i;
+  COMMAND *command;
+  char *word;
+
+  if (!line) return cmd_quit_(NULL);
+  
+  /* strip white  space */
+  line = g_strstrip(line);
+   
+  /* Isolate the command word. */
+  i = 0;
+  while (line[i] && isspace (line[i]))
+    i++;
+  word = line + i;
+     
+  while (line[i] && !isspace (line[i]))
+    i++;
+     
+  if (line[i])
+    line[i++] = '\0';
+     
+  command = find_command_ (word);
+     
+  if (!command)
+    {
+      fprintf (stderr, _("%s: No such command. Try \'help\'\n"), word);
+      return TRUE;
+    }
+     
+  /* Get argument to command, if any. */
+  while (isspace (line[i]))
+    i++;
+     
+  word = line + i;
+     
+  /* Call the function. */
+  return ((*(command->func)) (word));
+}
+     
+
diff --git a/mixutils/mixvm_command.h b/mixutils/mixvm_command.h
new file mode 100644
index 0000000..663aa41
--- /dev/null
+++ b/mixutils/mixvm_command.h
@@ -0,0 +1,38 @@
+/* -*-c-*- ---------------- mixvm_command.h :
+ * Declarations for commands accepted by the mix virtual machine
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIXVM_COMMAND_H
+#define MIXVM_COMMAND_H
+
+#include <glib.h>
+
+extern void
+mixvm_cmd_init (char *arg);
+
+extern gboolean
+mixvm_cmd_exec (char *line);
+
+
+
+
+#endif /* MIXVM_COMMAND_H */
+
diff --git a/mixutils/mixvm_loop.c b/mixutils/mixvm_loop.c
new file mode 100644
index 0000000..309c492
--- /dev/null
+++ b/mixutils/mixvm_loop.c
@@ -0,0 +1,66 @@
+/* -*-c-*- -------------- mixvm_loop.c :
+ * Implementation of mix vm command loop.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *  
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *  
+ */
+
+
+
+#include <mixlib/mix.h>
+#include <stdio.h>
+#include <readline/readline.h>
+#include <readline/history.h>
+#include "mixvm_command.h"
+
+/* A static variable for holding the line. */
+static char *line_read = (char *)NULL;
+static const char *PROMPT = N_("MIX > ");
+
+/* Read a string, and return a pointer to it.  Returns NULL on EOF. */
+static char *
+rl_gets ()
+{
+  /* If the buffer has already been allocated, return the memory
+     to the free pool. */
+  if (line_read)
+    {
+      g_free (line_read);
+      line_read = (char *)NULL;
+    }
+     
+  /* Get a line from the user. */
+  line_read = readline ((char *)PROMPT);
+     
+  /* If the line has any text in it, save it on the history. */
+  if (line_read && *line_read)
+    add_history (line_read);
+     
+  return (line_read);
+}
+
+
+/* The main command loop of the virtual machine  */
+void
+mix_vmloop (const gchar *file)
+{
+  mixvm_cmd_init ((char *)file);
+  while ( mixvm_cmd_exec (rl_gets ()) ) 
+    ;
+}
+
+
diff --git a/po/.cvsignore b/po/.cvsignore
new file mode 100644
index 0000000..c697044
--- /dev/null
+++ b/po/.cvsignore
@@ -0,0 +1,7 @@
+Makefile
+Makefile.in
+POTFILES
+ca.gmo
+cat-id-tbl.c
+mdk.pot
+stamp-cat-id
diff --git a/po/ChangeLog b/po/ChangeLog
new file mode 100644
index 0000000..7af10c3
--- /dev/null
+++ b/po/ChangeLog
@@ -0,0 +1,3 @@
+2000-02-08  jose antonio ortega ruiz  <jaortega@retemail.es>
+
+	* ca.po: New file
diff --git a/po/POTFILES.in b/po/POTFILES.in
new file mode 100644
index 0000000..8087956
--- /dev/null
+++ b/po/POTFILES.in
@@ -0,0 +1,10 @@
+# List of source files containing translatable strings.
+# Package source files
+mixutils/mixasm.c
+mixutils/mixasm_comp.c
+mixutils/mixvm.c
+mixutils/mixvm_command.c
+
+mixlib/mix_parser.c
+mixlib/mix_vm_dump.c
+
diff --git a/po/ca.po b/po/ca.po
new file mode 100644
index 0000000..32631da
--- /dev/null
+++ b/po/ca.po
@@ -0,0 +1,506 @@
+# file ca.po Catalan MIX translation
+# Copyright (C) 2000 jose antonio ortega ruiz <jaortega@retemail.es>
+#
+msgid ""
+msgstr ""
+"Project-Id-Version: mdk 0.1\n"
+"POT-Creation-Date: 2000-10-23 00:07+0200\n"
+"PO-Revision-Date: 2000-02-28 01:37+01:00\n"
+"Last-Translator: jose antonio ortega ruiz <jaortega@retemail.es>\n"
+"Language-Team: jose antonio ortega ruiz <jaortega@retemail.es>\n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=iso-8859-1\n"
+"Content-Transfer-Encoding: 8bit\n"
+
+#: mixutils/mixasm.c:52
+#, c-format
+msgid ""
+"Usage: %s [-vhulg] [-o OUTPUT_FILE] [--version] [--help]\n"
+"\t[--usage] [--debug] [--output=OUTPUT_FILE] [--list[=LIST_FILE]] file\n"
+msgstr ""
+"Ús: %s [-vhulg] [-o FIXTER_SORTIDA] [--version] [--help]\n"
+" [--usage] [--debug] [--output=FITXER_SORTIDA] [--list[=FITXER_LLISTAT]] "
+"FITXER\n"
+
+#: mixutils/mixasm.c:82
+#, c-format
+msgid "%s %s, MIX compiler.\n"
+msgstr "%s %s, Compilador de MIX.\n"
+
+#. getopt already handles the output of a warning message
+#: mixutils/mixasm.c:97 mixutils/mixvm.c:102
+#, c-format
+msgid "(Try: %s -h)\n"
+msgstr "(Proveu: %s -h)\n"
+
+#: mixutils/mixasm.c:106
+msgid "*** Error: Missing source file.\n"
+msgstr "*** Error: Fitxer font no trobat.\n"
+
+#: mixutils/mixasm.c:111 mixutils/mixvm.c:111
+msgid "*** Error: Too many input files.\n"
+msgstr "*** Error: Només es pot indicar un fitxer font.\n"
+
+#: mixutils/mixasm_comp.c:38
+#, c-format
+msgid "*** Unable to open source file %s\n"
+msgstr "*** Error obrint el fitxer font %s\n"
+
+#: mixutils/mixasm_comp.c:45
+#, c-format
+msgid "(%d warning(s))\n"
+msgstr "(%d advertències)\n"
+
+#: mixutils/mixasm_comp.c:48
+#, c-format
+msgid "*** Error writing output code file: %s\n"
+msgstr "*** Error obrint el fitxer de codi de sortida: %s\n"
+
+#: mixutils/mixasm_comp.c:56
+#, c-format
+msgid "*** Error writing listing file: %s\n"
+msgstr "*** Error obrint el fitxer de llistat: %s\n"
+
+#: mixutils/mixasm_comp.c:63
+#, c-format
+msgid "(%d warning(s), %d error(s))\n"
+msgstr "(%d advertències, %d errors)\n"
+
+#: mixutils/mixvm.c:59
+#, fuzzy, c-format
+msgid ""
+"Usage: %s [-vhurd] [--version] [--help] [--usage] [--run] [--dump] "
+"[MIX_FILE]\n"
+msgstr "Ús: %s [-vhu] [--version] [--help] [--usage] [FITXER_CODI]\n"
+
+#: mixutils/mixvm.c:89
+#, c-format
+msgid "%s %s, MIX Virtual Machine.\n"
+msgstr "%s %s, Màquina virtual de MIX.\n"
+
+#: mixutils/mixvm.c:134
+#, fuzzy, c-format
+msgid "Error loading %s file\n"
+msgstr "*** Error: Fitxer font no trobat.\n"
+
+#: mixutils/mixvm_command.c:74
+msgid "Display this text"
+msgstr "Aquest text"
+
+#: mixutils/mixvm_command.c:75
+msgid "Synonym for `help'"
+msgstr "Sinònim de help"
+
+#: mixutils/mixvm_command.c:76
+msgid "Execute shell command"
+msgstr "Executar comanda de shell"
+
+#: mixutils/mixvm_command.c:77
+msgid "Load a MIX code file"
+msgstr "Carregar en memòria un fitxer compilat"
+
+#: mixutils/mixvm_command.c:78
+msgid "Run loaded or given MIX code file"
+msgstr "Executar un fitxer de codi ja carregat o un donat"
+
+#: mixutils/mixvm_command.c:80
+msgid "Execute next instruction(s)"
+msgstr "Executar la següent instrucció"
+
+#: mixutils/mixvm_command.c:82
+msgid "Print program counter value"
+msgstr "Mostrar el valor actual del contador de programa"
+
+#: mixutils/mixvm_command.c:83
+msgid "Print symbol value"
+msgstr "Mostrar el valor d'un símbol donat"
+
+#: mixutils/mixvm_command.c:84
+msgid "Print register value"
+msgstr "Mostrar el valor d'un registre"
+
+#: mixutils/mixvm_command.c:86
+msgid "Print comparison and overflow flags"
+msgstr "Mostrar el valor dels flags de comparació i overflow"
+
+#: mixutils/mixvm_command.c:88
+msgid "Print all registers and flags"
+msgstr "Mostrar els valors de tots els registres i flags"
+
+#: mixutils/mixvm_command.c:89
+msgid "Print memory contents in address range"
+msgstr "Mostrar el contingut de la memòria en un rang d'adreces"
+
+#: mixutils/mixvm_command.c:91
+msgid "Set register value"
+msgstr "Donar un valor a un registre"
+
+#: mixutils/mixvm_command.c:93
+msgid "Set comparison flag value"
+msgstr "Donar un valor al flag de comparació"
+
+#: mixutils/mixvm_command.c:94
+msgid "Set overflow flag value"
+msgstr "Donar un valor al flag d'overflow"
+
+#: mixutils/mixvm_command.c:95
+msgid "Set memory contents in given address"
+msgstr "Donar un valor al contingut d'una adreça de memòria"
+
+#: mixutils/mixvm_command.c:97
+msgid "Set break point at given line"
+msgstr "Establir un punt de ruptura"
+
+#: mixutils/mixvm_command.c:98
+msgid "Clear break point at given line"
+msgstr "Esborrar un punt de ruptura"
+
+#: mixutils/mixvm_command.c:99
+#, fuzzy
+msgid "Set break point at given address"
+msgstr "Establir un punt de ruptura"
+
+#: mixutils/mixvm_command.c:101
+#, fuzzy
+msgid "Clear break point at given address"
+msgstr "Esborrar un punt de ruptura"
+
+#: mixutils/mixvm_command.c:103
+msgid "Clear all breakpoints"
+msgstr "Esborrar tots els punts de ruptura"
+
+#: mixutils/mixvm_command.c:104
+msgid "Compile a source file"
+msgstr "Compilar un fitxer font"
+
+#: mixutils/mixvm_command.c:105
+msgid "Edit a source file"
+msgstr "Editar un fitxer font"
+
+#: mixutils/mixvm_command.c:106
+msgid "Quit the program"
+msgstr "Sortir"
+
+#: mixutils/mixvm_command.c:199
+#, c-format
+msgid "%s\t\t%s. Usage: %s\n"
+msgstr "%s              %s. Ús: %s\n"
+
+#: mixutils/mixvm_command.c:207
+#, c-format
+msgid "No commands match `%s'.  Possibilities are:\n"
+msgstr "Cap comanda amb nom %s. Les possibilitats són:\n"
+
+#: mixutils/mixvm_command.c:232
+msgid "Missing file name\n"
+msgstr "Especifiqueu nom de fitxer\n"
+
+#: mixutils/mixvm_command.c:235
+#, c-format
+msgid "Cannot load %s: "
+msgstr "No es pot carregar %s: "
+
+#: mixutils/mixvm_command.c:237
+msgid "Wrong file format\n"
+msgstr "El fitxer no té un format correcte\n"
+
+#: mixutils/mixvm_command.c:242
+#, c-format
+msgid "Program loaded. Start address: %d\n"
+msgstr "Programa carregat. Adreça d'inici: %d\n"
+
+#: mixutils/mixvm_command.c:253
+msgid "Running ..."
+msgstr "Executant programa ..."
+
+#: mixutils/mixvm_command.c:257
+msgid "... done"
+msgstr "... fet"
+
+#: mixutils/mixvm_command.c:263
+#, c-format
+msgid "... stopped: breakpoint at line %ld (address %d)\n"
+msgstr "... interromput: put de ruptura a la línia %ld (adreça %d)\n"
+
+#: mixutils/mixvm_command.c:266
+#, fuzzy, c-format
+msgid "... stopped: breakpoint at address %d\n"
+msgstr "... interromput: put de ruptura a la línia %ld (adreça %d)\n"
+
+#: mixutils/mixvm_command.c:271
+msgid "... error executing loaded file"
+msgstr "... error executant el fitxer carregat"
+
+#: mixutils/mixvm_command.c:291 mixutils/mixvm_command.c:393
+#: mixutils/mixvm_command.c:454 mixutils/mixvm_command.c:521
+#: mixutils/mixvm_command.c:548 mixutils/mixvm_command.c:572
+#: mixutils/mixvm_command.c:626 mixutils/mixvm_command.c:656
+#: mixutils/mixvm_command.c:683 mixutils/mixvm_command.c:716
+#: mixutils/mixvm_command.c:741
+#, c-format
+msgid "Invalid argument: %s\n"
+msgstr "Argument no vàlid: %s\n"
+
+#: mixutils/mixvm_command.c:302
+#, c-format
+msgid "End of program reached at address %d\n"
+msgstr "Fi del programa a l'adreça %d\n"
+
+#: mixutils/mixvm_command.c:308
+#, c-format
+msgid "Error at address %d\n"
+msgstr "Error a l'adreça: %d\n"
+
+#: mixutils/mixvm_command.c:338
+msgid "Symbol table not available\n"
+msgstr "Taula de símbols no disponible\n"
+
+#: mixutils/mixvm_command.c:347
+#, c-format
+msgid "%s: symbol not defined\n"
+msgstr "El símbol %s no està definit\n"
+
+#: mixutils/mixvm_command.c:385
+#, c-format
+msgid "Invalid I index: %d"
+msgstr "Camp d'índex %d no vàlid"
+
+#: mixutils/mixvm_command.c:425
+msgid "Missing memory address\n"
+msgstr "Especifiqueu l'adreça de memòria\n"
+
+#: mixutils/mixvm_command.c:459
+#, c-format
+msgid "Invalid range: %ld-%ld\n"
+msgstr "Rang %ld-%ld no vàlid\n"
+
+#: mixutils/mixvm_command.c:633
+#, c-format
+msgid "Line number %ld too high\n"
+msgstr "Número de línia %ld massa alt\n"
+
+#: mixutils/mixvm_command.c:636 mixutils/mixvm_command.c:666
+#: mixutils/mixvm_command.c:693
+msgid "Could not set breakpoint. Internal error\n"
+msgstr "Error intern intentant establir un punt de ruptura\n"
+
+#: mixutils/mixvm_command.c:639
+msgid "Could not set breakpoint. No debug info available\n"
+msgstr "No es pot establir el punt de ruptura. No hi ha informació de debug\n"
+
+#: mixutils/mixvm_command.c:642
+#, c-format
+msgid "Breakpoint set at line %ld\n"
+msgstr "Punt de ruptura a la línia %ld establert\n"
+
+#: mixutils/mixvm_command.c:663 mixutils/mixvm_command.c:723
+#, fuzzy, c-format
+msgid "Invalid address %ld\n"
+msgstr "camp d'adreça no vàlid"
+
+#: mixutils/mixvm_command.c:669
+#, fuzzy, c-format
+msgid "Breakpoint set at address %ld\n"
+msgstr "Punt de ruptura a la línia %ld establert\n"
+
+#: mixutils/mixvm_command.c:690
+#, c-format
+msgid "No breakpoint set at line %ld\n"
+msgstr "No hi havia cap punt de ruptura a la línia %ld\n"
+
+#: mixutils/mixvm_command.c:696
+msgid "No debug info available\n"
+msgstr "No hi ha informació de debug disponible\n"
+
+#: mixutils/mixvm_command.c:699
+#, c-format
+msgid "Breakpoint cleared at line %ld\n"
+msgstr "Punt de ruptura esborrat a la línia %ld\n"
+
+#: mixutils/mixvm_command.c:726
+#, fuzzy
+msgid "Could not clear breakpoint. Internal error\n"
+msgstr "Error intern intentant establir un punt de ruptura\n"
+
+#: mixutils/mixvm_command.c:729
+#, fuzzy, c-format
+msgid "Breakpoint cleared at address %ld\n"
+msgstr "Punt de ruptura esborrat a la línia %ld\n"
+
+#: mixutils/mixvm_command.c:765
+msgid "Successful compilation\n"
+msgstr "La compilació s'ha completat amb éxit\n"
+
+#: mixutils/mixvm_command.c:820
+msgid "Failed initialisation (no memory resources)"
+msgstr "Error inicialitzant programa (no hi ha memòria)"
+
+#: mixutils/mixvm_command.c:853
+#, c-format
+msgid "%s: No such command. Try 'help'\n"
+msgstr "La comanda %s no existeix. Proveu 'help'\n"
+
+#: mixlib/mix_parser.c:35
+msgid "successful compilation"
+msgstr "La compilació s'ha completat amb éxit"
+
+#: mixlib/mix_parser.c:36
+msgid "file not yet compiled"
+msgstr "el fitxer encara no està compilat"
+
+#: mixlib/mix_parser.c:37
+msgid "internal error"
+msgstr "error intern"
+
+#: mixlib/mix_parser.c:38
+msgid "unable to open MIX source file"
+msgstr "no s'ha pogut obrir el fitxer font"
+
+#: mixlib/mix_parser.c:39
+msgid "unable to open MIX output file"
+msgstr "no s'ha pogut obrir el fitxer per a escritura"
+
+#: mixlib/mix_parser.c:40
+msgid "unexpected end of file"
+msgstr "fi de fitxer inesperat"
+
+#: mixlib/mix_parser.c:41
+msgid "invalid location field"
+msgstr "invalid camp 'location'"
+
+#: mixlib/mix_parser.c:42
+msgid "duplicated symbol"
+msgstr "símbol duplicat"
+
+#: mixlib/mix_parser.c:43
+msgid "symbol too long"
+msgstr "símbol massa llarg"
+
+#: mixlib/mix_parser.c:44
+msgid "missing operator field"
+msgstr "falta l'indicador d'operació"
+
+#: mixlib/mix_parser.c:45
+msgid "unexpected location symbol"
+msgstr "símbol local inesperat"
+
+#: mixlib/mix_parser.c:46
+msgid "invalid address field"
+msgstr "camp d'adreça no vàlid"
+
+#: mixlib/mix_parser.c:47
+msgid "invalid index field"
+msgstr "camp d'índex no vàlid"
+
+#: mixlib/mix_parser.c:48
+msgid "invalid f-specification"
+msgstr "especificació de camp ('f-spec') no vàlida"
+
+#: mixlib/mix_parser.c:49
+msgid "invalid operation field"
+msgstr "camp d'operació no vàlid"
+
+#: mixlib/mix_parser.c:50
+msgid "invalid expression"
+msgstr "expressió errònia"
+
+#: mixlib/mix_parser.c:51
+msgid "undefined symbol"
+msgstr "símbol no definit"
+
+#: mixlib/mix_parser.c:52
+msgid "mismatched parenthesis"
+msgstr "paréntesi sense tancar"
+
+#: mixlib/mix_parser.c:53
+msgid "unexpected f-specfication"
+msgstr "especificació de camp ('f-spec') inesperada"
+
+#: mixlib/mix_parser.c:54
+msgid "missing symbol name"
+msgstr "nom del símbol absent"
+
+#: mixlib/mix_parser.c:55
+msgid "symbol is an instruction name"
+msgstr "el nom de símbol coincideix amb un nom d'operació"
+
+#: mixlib/mix_parser.c:56
+msgid "failed write access to code file"
+msgstr "error mentre s'escrivia el fitxer de codi"
+
+#: mixlib/mix_parser.c:57
+msgid "operand of ALF pseudo instruction has less than 5 chars"
+msgstr ""
+
+#: mixlib/mix_parser.c:58
+msgid "operand of ALF pseudo instruction has more than 5 chars"
+msgstr ""
+
+#: mixlib/mix_parser.c:121 mixlib/mix_parser.c:139
+msgid "No system resources"
+msgstr "no hi ha recursos al sistema"
+
+#: mixlib/mix_parser.c:324
+#, c-format
+msgid "\t%s\t(line %d)\n"
+msgstr "        %s      (línia %d)\n"
+
+#: mixlib/mix_parser.c:343
+#, c-format
+msgid ""
+"*** %s%s: compilation summary ***\n"
+"\n"
+msgstr ""
+"*** %s%s: resum de la compilació\n"
+"\n"
+
+#: mixlib/mix_parser.c:346
+msgid "*** Address / Compiled word / Symbolic rep / Source file line\n"
+msgstr "*** Adreça / Paraula compilada / Repr. simbólica / Núm. línia\n"
+
+#: mixlib/mix_parser.c:350
+#, c-format
+msgid ""
+"\n"
+"*** Start address: %d\n"
+msgstr ""
+"\n"
+"*** Adreça d'inici: %d\n"
+
+#: mixlib/mix_parser.c:352
+msgid ""
+"\n"
+"*** Symbol table\n"
+msgstr ""
+"\n"
+"*** Taula de símbols\n"
+
+#: mixlib/mix_parser.c:354
+msgid ""
+"\n"
+"*** End of summary ***\n"
+msgstr ""
+"\n"
+"*** Fi del resum ***\n"
+
+#: mixlib/mix_parser.c:484
+msgid "Unable to allocate memory"
+msgstr "Memòria dinàmica insuficient"
+
+#: mixlib/mix_parser.c:512
+msgid "warning"
+msgstr "advertència"
+
+#: mixlib/mix_parser.c:512
+msgid "error"
+msgstr "error"
+
+#: mixlib/mix_vm_dump.c:155
+#, c-format
+msgid "Overflow: %s\n"
+msgstr "Overflow: %s\n"
+
+#: mixlib/mix_vm_dump.c:179
+#, c-format
+msgid "Cmp: %s\n"
+msgstr "Cmp: %s\n"
diff --git a/samples/.cvsignore b/samples/.cvsignore
new file mode 100644
index 0000000..4e88a5a
--- /dev/null
+++ b/samples/.cvsignore
@@ -0,0 +1,25 @@
+Makefile
+Makefile.in
+cardwr.dev
+disk0.dev
+disk1.dev
+disk2.dev
+disk3.dev
+disk4.dev
+disk5.dev
+disk6.dev
+disk7.dev
+hello.mix
+hello.mls
+paper.dev
+primes.mix
+primes.mls
+printer.dev
+tape0.dev
+tape1.dev
+tape2.dev
+tape3.dev
+tape4.dev
+tape5.dev
+tape6.dev
+tape7.dev
diff --git a/samples/Makefile.am b/samples/Makefile.am
new file mode 100644
index 0000000..64b7e09
--- /dev/null
+++ b/samples/Makefile.am
@@ -0,0 +1,14 @@
+## Process this file with automake to produce Makefile.in
+
+# Copyright (C) 2000 Jose Antonio Ortega Ruiz <jaortega@retemail.es>
+#  
+# This file is free software; as a special exception the author gives
+# unlimited permission to copy and/or distribute it, with or without 
+# modifications, as long as this notice is preserved.
+# 
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+EXTRA_DIST =*.mix 
+
diff --git a/samples/hello.mixal b/samples/hello.mixal
new file mode 100644
index 0000000..6a4c3c1
--- /dev/null
+++ b/samples/hello.mixal
@@ -0,0 +1,11 @@
+* mixal hello world
+*
+TERM	EQU	19
+	ORIG	3000
+START	OUT	MSG(TERM)
+	HLT
+MSG	ALF	"MIXAL"
+	ALF	" HELL"
+	ALF	"O WOR"
+	ALF	"LD   "
+	END	START
diff --git a/samples/primes.mixal b/samples/primes.mixal
new file mode 100644
index 0000000..d2de8c0
--- /dev/null
+++ b/samples/primes.mixal
@@ -0,0 +1,53 @@
+* table of primes (taopc p. 148)
+*
+L	EQU	500
+OUTDEV	EQU	20	the paper tape
+PRIME	EQU	-1
+BUF0	EQU	2000
+BUF1	EQU	BUF0+25
+	ORIG	3000
+START	IOC	0(OUTDEV)
+	LD1	=1-L=
+	LD2	=3=
+2H	INC1	1
+	ST2	PRIME+L,1
+	J1Z	2F
+4H	INC2	2
+	ENT3	2
+6H	ENTA	0
+	ENTX	0,2
+	DIV	PRIME,3
+	JXZ	4B
+	CMPA	PRIME,3
+	INC3	1
+	JG	6B
+	JMP	2B
+2H	OUT	TITLE(OUTDEV)
+	ENT4	BUF1+10
+	ENT5	-50
+2H	INC5	L+1
+4H	LDA	PRIME,5
+	CHAR
+	STX	0,4(1:4)
+	DEC4	1
+	DEC5	50
+	J5P	4B
+	OUT	0,4(OUTDEV)
+	LD4	24,4
+	J5N	2B
+	HLT
+* initial contents
+	ORIG	PRIME+1
+	CON	2
+	ORIG	BUF0-5
+TITLE	ALF	"FIRST"
+	ALF	" FIVE"
+	ALF	" HUND"
+	ALF	"RED P"
+	ALF	"RIMES"
+	ORIG	BUF0+24
+	CON	BUF1+10
+	ORIG	BUF1+24
+	CON	BUF0+10
+	END	START
+
-- 
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