		Last Updated:  January 29, 2010

The S-Lang GIF module provides a high-level interface to the GIF file
format, supporting the easy creation of S-Lang arrays from GIF files
and vice versa.  One of the most useful features of the module is that
it provides a lightweight mechanism for reading & writing frames of
images as movie-like animations, in vectorized fashion: multiple frame
images may be written to, or read from, a GIF file in a single call.
Low-level I/O is handled internally through bindings to GIFSICLE, much
of which may be called directly from SLgif, although most users
should only need the gif_read() and gif_write() functions.

To build the S-Lang GIF module you will need the S-Lang interpreter
installed.  Many modern systems will already contain S-Lang (e.g.
Linux distributions), but if yours does not it may be obtained from

   	http://www.s-lang.org
   	http://www.jedsoft.org/slang

For user convenience a library version of GIFSICLE is bundled with the
SLgif distribution, so GIFSICLE does not need to be downloaded or
installed separately.

You must run the configure script before you can compile the
distribution.  If you are either unfamiliar with this process,
or would like to customize the build/installation, run

  ./configure --help

The default module installation location is

   $prefix/lib/slang/modules/		SLang 1
   $prefix/lib/slang/v2/modules/	SLang 2

By default the .sl scripts will be installed in

   $exec_prefix/share/slsh/local-packages/

where the value of $prefix defaults to /usr/local and that of $exec_prefix
to $prefix.  These values may be changed using the --prefix and
--exec-prefix configure script parameters.

For example, to set the value of $prefix to /home/bill, use

   ./configure --prefix=/home/bill ...

Once the configure script has been run, it is a good idea to inspect
the Makefile that it generated in the src directory.  Then building
and installing the library should involve nothing more than:

   make 
   make install

You may need to have root privileges to perform the last step.

Plain text documentation for the package can be found in the doc directory.

The ./tests subdirectory contains a suite of regression test scripts which
may be exercised in the usual manner:

   make test

These scripts are also a good source of usage examples.
