INSTALL - information about source, compilation etc.
----------------------------------------------------

Svgalib is required for zgv to compile. The program should work with
any reasonably recent version, but I strongly recommend you use
svgalib 1.3.1 or later to avoid a few bugs which were present in
earlier releases (in any case, you should not use version 1.2.10 or
earlier due to a potential security risk). You can find svgalib on
metalab.unc.edu in /pub/Linux/libs/graphics.

The Independent JPEG Group's JPEG software is also required for zgv to
compile. The README in v6b of the JPEG software says:

"The "official" archive site for this software is ftp.uu.net (Internet
address 192.48.96.9).  The most recent released version can always be found
there in directory graphics/jpeg.  This particular version will be archived
as ftp://ftp.uu.net/graphics/jpeg/jpegsrc.v6b.tar.gz."

...so look there for the source.

Once you've got it, do `./configure', then `make libjpeg.a', and also
make sure JPEGDIR in zgv's `config.mk' is set to the directory you
have the JPEG software's source in.

(By the way, you must use at least version 5 of the library - version
4 is now not supported, as the library underwent quite a rewrite
between versions 4 and 5. Versions 5, 5a, 6, 6a, and 6b should all
work, but it's probably best to use the latest one.)


If you want PNG support, you'll need:

ftp://ftp.uu.net/graphics/png/code/lpng???.zip	and
ftp://ftp.uu.net/graphics/png/code/zlib???.zip

...where the ?'s are the version number. (The dirs/filenames might be
different now - libpng should be under /graphics/png somewhere though,
and zlib should be either there or in /pub/archiving/zip/zlib.)
Alternatively, most Linux distributions will probably include the
source to both libpng and zlib.

If you don't want PNG support, comment out the `PNGDEF' line in
`config.mk' and skip ahead to the `When libraries are in place'
heading below. In case you don't know what the PNG format is (which
seems unlikely these days :-)), here's an extract from the format
specification:

> The PNG format is intended to provide a portable, legally
> unencumbered, well-compressed, well-specified standard for lossless
> bitmapped image files. 
> 
> Although the initial motivation for developing PNG was to replace GIF,
> the design provides some useful new features not available in GIF, with
> minimal cost to developers. 

The process of building the libpng and zlib libraries goes something
like this, assuming both the zip files are in /usr/src (and assuming
you have `unzip' installed):

cd /usr/src
mkdir libpng zlib
cd zlib;unzip -a ../zlib*.zip
./configure
make libz.a
cd ../libpng;unzip -a ../lpng*.zip
make -f scripts/makefile.lnx libpng.a

Be sure to use the `-a' option to unzip as otherwise the text files
will be left in MS-DOS CR/LF format which will result in suitably
bizarre error messages.


When libraries are in place
---------------------------

When you've done that you should have a overall check through
`config.mk' if you haven't already, to see if it all looks ok. (Though
you may want to change PREFIX if you want the files to go somewhere
other than /usr/bin, /usr/info, etc.)

Then do `make', and (as root) `make install'. This compiles zgv, then
installs it and its documentation (both info files and man page).

Good luck!

-Rus.
