1This directory contains the zlib package, which is not part of GCC but
2shipped with GCC as convenience.
3
4ZLIB DATA COMPRESSION LIBRARY
5
6zlib 1.2.8 is a general purpose data compression library.  All the code is
7thread safe.  The data format used by the zlib library is described by RFCs
8(Request for Comments) 1950 to 1952 in the files
9http://tools.ietf.org/html/rfc1950 (zlib format), rfc1951 (deflate format) and
10rfc1952 (gzip format).
11
12All functions of the compression library are documented in the file zlib.h
13(volunteer to write man pages welcome, contact zlib@gzip.org).  A usage example
14of the library is given in the file test/example.c which also tests that
15the library is working correctly.  Another example is given in the file
16test/minigzip.c.  The compression library itself is composed of all source
17files in the root directory.
18
19To compile all files and run the test program, follow the instructions given at
20the top of Makefile.in.  In short "./configure; make test", and if that goes
21well, "make install" should work for most flavors of Unix.  For Windows, use
22one of the special makefiles in win32/ or contrib/vstudio/ .  For VMS, use
23make_vms.com.
24
25Questions about zlib should be sent to <zlib@gzip.org>, or to Gilles Vollant
26<info@winimage.com> for the Windows DLL version.  The zlib home page is
27http://zlib.net/ .  Before reporting a problem, please check this site to
28verify that you have the latest version of zlib; otherwise get the latest
29version and check whether the problem still exists or not.
30
31PLEASE read the zlib FAQ http://zlib.net/zlib_faq.html before asking for help.
32
33Mark Nelson <markn@ieee.org> wrote an article about zlib for the Jan.  1997
34issue of Dr.  Dobb's Journal; a copy of the article is available at
35http://marknelson.us/1997/01/01/zlib-engine/ .
36
37The changes made in version 1.2.8 are documented in the file ChangeLog.
38
39Unsupported third party contributions are provided in directory contrib/ .
40
41zlib is available in Java using the java.util.zip package, documented at
42http://java.sun.com/developer/technicalArticles/Programming/compression/ .
43
44A Perl interface to zlib written by Paul Marquess <pmqs@cpan.org> is available
45at CPAN (Comprehensive Perl Archive Network) sites, including
46http://search.cpan.org/~pmqs/IO-Compress-Zlib/ .
47
48A Python interface to zlib written by A.M. Kuchling <amk@amk.ca> is
49available in Python 1.5 and later versions, see
50http://docs.python.org/library/zlib.html .
51
52zlib is built into tcl: http://wiki.tcl.tk/4610 .
53
54An experimental package to read and write files in .zip format, written on top
55of zlib by Gilles Vollant <info@winimage.com>, is available in the
56contrib/minizip directory of zlib.
57
58
59Notes for some targets:
60
61- For Windows DLL versions, please see win32/DLL_FAQ.txt
62
63- For 64-bit Irix, deflate.c must be compiled without any optimization. With
64  -O, one libpng test fails. The test works in 32 bit mode (with the -n32
65  compiler flag). The compiler bug has been reported to SGI.
66
67- zlib doesn't work with gcc 2.6.3 on a DEC 3000/300LX under OSF/1 2.1 it works
68  when compiled with cc.
69
70- On Digital Unix 4.0D (formely OSF/1) on AlphaServer, the cc option -std1 is
71  necessary to get gzprintf working correctly. This is done by configure.
72
73- zlib doesn't work on HP-UX 9.05 with some versions of /bin/cc. It works with
74  other compilers. Use "make test" to check your compiler.
75
76- gzdopen is not supported on RISCOS or BEOS.
77
78- For PalmOs, see http://palmzlib.sourceforge.net/
79
80
81Acknowledgments:
82
83  The deflate format used by zlib was defined by Phil Katz.  The deflate and
84  zlib specifications were written by L.  Peter Deutsch.  Thanks to all the
85  people who reported problems and suggested various improvements in zlib; they
86  are too numerous to cite here.
87
88Copyright notice:
89
90 (C) 1995-2013 Jean-loup Gailly and Mark Adler
91
92  This software is provided 'as-is', without any express or implied
93  warranty.  In no event will the authors be held liable for any damages
94  arising from the use of this software.
95
96  Permission is granted to anyone to use this software for any purpose,
97  including commercial applications, and to alter it and redistribute it
98  freely, subject to the following restrictions:
99
100  1. The origin of this software must not be misrepresented; you must not
101     claim that you wrote the original software. If you use this software
102     in a product, an acknowledgment in the product documentation would be
103     appreciated but is not required.
104  2. Altered source versions must be plainly marked as such, and must not be
105     misrepresented as being the original software.
106  3. This notice may not be removed or altered from any source distribution.
107
108  Jean-loup Gailly        Mark Adler
109  jloup@gzip.org          madler@alumni.caltech.edu
110
111If you use the zlib library in a product, we would appreciate *not* receiving
112lengthy legal documents to sign.  The sources are provided for free but without
113warranty of any kind.  The library has been entirely written by Jean-loup
114Gailly and Mark Adler; it does not include third-party code.
115
116If you redistribute modified sources, we would appreciate that you include in
117the file ChangeLog history information documenting your changes.  Please read
118the FAQ for more information on the distribution of modified source versions.
119