Description of GCL (GNU Common Lisp) system.

OVERVIEW:

The GCL system contains C and Lisp source files to build a Common Lisp
sytem.  The original KCL system was written by Taiichi Yuasa and
Masami Hagiya in 1984.  The AKCL system work was begun in 1987 by
William Schelter and continued through 1994.  A number of people have
contributed ports and pieces.  The file doc/contributors lists some of
these.  In 1994 AKCL was released as GCL (GNU Common Lisp) under the
GNU public library license.  Version akcl-1-624 was the last version
made under the old license and using the old file change mechanism.
This readme only applies to versions gcl.1.0 and later.  The GNU
library license does allow redistribution of executables containing
GCL as well as proprietary code, but such redistribution must be
accompanied by sufficient material (eg .o files) to allow recipients
to rebuild an executable, after possibly modifying GCL.  See the GNU
file COPYING.LIB-2.0 for a full description of your right to copy this
software.

Releases of GCL after 2.0 contain a GCL connection with the windowing
tools TCL/TK.  If 'configure' is able to find the relevant libraries on
your system, then a gcl-tk server will be compiled as well by the main
make.  It is based on TK 8.0 and TCL 8.0 and available from
ftp.cs.berkeley.edu and many mirrors.   


OBTAINING SOURCES:
-----------------

* There are source files on ftp.ma.utexas.edu:pub/gcl/gcl.x.x.tgz You
probably want the highest XX version number.  For example gcl-1.0.tgz
would allow you to build the version 1.0 of GCL.  In the following
this compressed tar file is simply referred to as gcl.tgz.  If you
do not have gzip it is available in the directory
/anyonymous@prep.ai.mit.edu:/u2/emacs .
Hopefully sometime, GCL will also be available on prep.ai.mit.edu.
				   

MAKING THE SYSTEM:
==================
To make the whole system, if you have obtained gcl.tgz. 

UNCOMPRESS and UNTAR the SOURCES:
--------------------------------

Change to a directory in which you wish to build gcl, eg ~/tmp.
Copy the file gcl.tgz to this directory.

	% gzip -dc gcl.tgz | tar  xvf -

This will create the subdirectory gcl-y.xxx with all the sources in it.

      
ADD MACHINE DEFINITIONS TO MAKEFILES:
------------------------------------

	% cd gcl-y.xxx 
	% ./configure

This will analyze your system, generate a file called makedefs, insert
it into the various makefiles and create a proper h/config.h header
file for your system.

Some command line options can be used with the configure script; try
./configure --help to find out about them.

Note that if you have tcl/tk (version 4.2 tk or 7.6 tcl or later),
then a file tclConfig.sh and tkConfig.sh should exist in some place
such as /usr/local/lib.  


RUNNING MAKE:
------------

	% make

The make should continue without error.   There may be occasional
warnings from the C compiler, but all files should compile successfully
producing .o files.

At the end you should see a message at the end "Make of GCL xxx
completed", where xxx stands for the version number. Every successful
compilation generates an automatic notification email to
gcl@math.utexas.edu to help in determininig on which machines and
levels of the OS compilation has been successful. If you don't want to
assist in the maintenance in this way do
        
	% ./configure  --enable-notify=no

before make.


TRY IT OUT:
----------

When it has finally finished you may invoke GCL by using

% xbin/gcl
GCL (GNU Common Lisp)  Version(2.3) Sun May  7 14:11:30 CDT 2000
Licensed under GNU Library General Public License
Contains Enhancements by W. Schelter

>(+ 2 3)

>5

If you had TCL/TK, then you should be able to do
>(si::tkconnect)
>(load "gcl-tk/demos/widget.lisp")

Note there are currently problems with the demos, since they were
based on an older version of tcl/tk.
(setq si::*tk-library* "/usr/lib/tk")
[where /usr/lib/tk/tk.tcl is]


INSTALLING:
----------

	To install under /usr/local (or under the directory specified
        with the --prefix= option of the ./configure script)

	% make install

	The default installation puts a full executable in

	  /usr/local/lib/gcl-version/unixport/saved_gcl

	and some documentation in
          
	  /usr/local/lib/gcl-x.x/info/

	and some autoloading files in

	  /usr/local/lib/gcl-x.x/lsp

        and a shell script in 
	  
	  /usr/local/lib/gcl-x.x/xbin/gcl

	This script is also copied to

	  /usr/local/bin


FUTURE DIRECTIONS
=================
(and how you may be able to help)   Volunteers should contact
William Schelter (wfs@math.utexas.edu)

a) Upgrading to comply with the forthcoming ANSI standard.   Work 
needs to be done.   

b) Need work on providing a high level window interface.   One possible
way would be a good connection with TCL/TK.   Another would be to go
in the direction of CLIM.   

A new compiler has been written, which is closer to the ANSI standard
and provides some other benefits.   It will be in a future release.
We will need people willing to beta test and isolate any bugs.

Additonal work planned or desired:

  * Clean up distribution and installation.  Make it easier to link in
C code such as Novak's window stuff.   Faslink is not portable (since
many systems don't support ld -A).

  * Introduce COMMON-LISP and COMMON-LISP-USER packages as per ANSI
standard, change the package functions to behave as in the ANSI
standard.  Any other changes which people can identify which would
make life easier, and are compatible with ANSI.

  * Introduce C level and Lisp level way of signalling errors of the
types specified by the ANSI standard.  Make it so that when the CLOS
is present these become error objects.

  * Fix the run-process stuff to properly deallocate processes and
have listen do the right thing, by using select, which is POSIX.  Try
to make it compatible with the one in Allegro or Lucid.

Done  * Turn ANSI documentation into the new Lisp's on-line documentation.
This will be useful for development and for users.  No sense in basing
our work on the CLTL 2.  Must go to the ANSI document itself.

  * Make an appropriate Unix man page.

  * Add my allocation files and other changes necessary to make
INTERRUPTS safe.  This probably means adding in all the C files which
I have already written.

  * Change function calls to all refer to C stack and pass return
values in a uniform way, the way the new compiler does it.  This will
greatly improve funcalling, since right now there are generally two
types of functions which can be expected, and they expect their
arguments in different places.

  * Change to the new compiler which does things better from the ANSI
point of view, and is smaller, and makes all function calls go via the
C stack.

  * Include CLOS support.  Possibly take this from PCL or from
Attardi, who has written some.

 Done  * Include a windowing interface with TCL/TK which is capable of
producing TK (similar to Motif but public) style windows and
scrollable menus, etc.  This implementation must be done in such a way
that it works in at least one additional Lisp, such as Allegro or
Lucid.

  * Loop package: either make sloop satisfy the standard or include
another implementation.

  * Changes to READ for ANSI, (including case sensitivity, etc.).

  * Byte compiler based on first pass of the new compiler.  Ideally
provides very small code and extremely rapid compiling for general
platform.  Notes: I have put the interrupt and run-process stuff early
on since it is necessary for window development.

  * Construct a Common Lisp test suite to help debug new releases.


DOCUMENTATION:
==============
   If you use GNU emacs, a convenient method for viewing documentation
of Common Lisp functions (or functions in an extended system), is
provided by the doc/find-doc.el file.  This will be installed when you
do make in the doc directory.  Adding the following to your .emacs
file will allow you to use C-h d to find documentation.

(autoload 'find-doc "find-doc" nil t)
(global-set-key "d" 'find-doc)
(visit-doc-file "/usr/local/lib/gcl/doc/DOC")

See the file find-doc.el for more information.  Otherwise you may use
the describe command inside Lisp.  For example (describe 'print) will
print out information about print.  It will access the gcl-si.info,
gcl-tk.info, and gcl.info if these exist.  gcl.info (containing the
ansi proposed definitions) is on ftp.ma.utexas.edu:pub/gcl/gcl.info.tgz


TROUBLE SHOOTING (some common problems reported):
----------------   

1) Did you extract the files with the original write dates--make
depends heavily on this?

2) Did you use -O on a compiler which puts out bad code?  Any time you
change the settings or use a new c compiler this is a tricky point.

3) If you can't save an image, try doing so on the file server rather
than a client.

4) Doing the make on a client with the main files on a server, has
sometimes caused random breakage.  The large temp files used by the C
compiler seem to sometimes get transferred incorrectly.  Solution: use
the server for the compile.

5) Did you make changes in the .defs or .h files, other than just
commenting out a CC=gcc line?

6) Did you read the recommendations in the XXXX.defs file on what
C compiler versions work?

7) (si::tkconnect) fails:
   a) Make sure DISPLAY variable set before
starting gcl.
   b) gcltkaux (subsidiary process) uses shared libraries and
you would need LD_LIBRARY_PATH set on say suns, to say where those are
if they are not in default places. [make sure "wish" would work]


CHANGING THINGS: MAYBE EDIT THREE FILES:
--------------------

Normally you should not need to edit ANY files.  There may be some
parameter sizes you wish to change or if you don't have gcc where
we have made that the default, then see CC below.


EDIT the ./add-defs script

If when you do `add-defs machine` the add-defs script is not able to
find directories where things like tk.h, libX11.a etc are, then it
will print out a message.  You can to have it look in some extra
places on your machine, or in a different order.   Note that if it
fails to find these things the tcl/tk support will not be built, but
you will have an ordinary common lisp.


EDIT the appropriate h/NAME.defs file.   These are definitions to
be included in the various makefiles.

For example if the `NAME' of your machine is sun3-os4.

% emacs h/sun3-os4.defs

   * CC: set C compiler options.  For example, if you are using the GNU
     C compiler:

     CC = gcc -msoft-float -DVOL=volatile -I$(GCLDIR)/o

         Or, if you are using the conventional UNIX C compiler:

     CC = cc -DVOL= -I. -I$(GCLDIR)/o
     
   * ODIR_DEBUG:
     
     ODIR_DEBUG= -g

     If you want files in the main c source compiled with debugging
     information.   Note this is incompatible with OFLAGS= -O on
     some compilers.   Size will be smaller without -g, but you
     are then helpless in the face of problems.
     
   * INITFORM: The normal thing is to just have the one form
     required for fast loading.

    INITFORM=(si::build-symbol-table)


-----------

EDIT the file h/NAME.h  (eg h/sun3-os4.h)

(Actually you probably don't need to change it)

This file will be included by virtually every compilation of C
files, except the translated C produced by kcl.

% emacs h/sun3-os4.h

      if you wish to change a parameter such as MAXPAGE 16384 established
      in bsd.h (ie. number of 2000 byte pages you want as your absolute max
      swap space).   MAXPAGE must be a power of 2.

      #undef MAXPAGE
      #define MAXPAGE (2 * 16384)

      You may similarly redefine VSSIZE the maximum size for the value
      stack (running very deep recursion interpreted may well require this).



DISCLAIMER:
----------

W. Schelter, the University of Texas, and other parties provide this
program on an "as is" basis 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.


Bill Schelter 
wfs@math.utexas.edu

See the file doc/contributors for a partial list of people who have
made helpful contributions to ports etc.
