1 This directory contains the zlib package, which is not part of GCC but
2 shipped with GCC as convenience.
4 ZLIB DATA COMPRESSION LIBRARY
6 zlib 1.2.1 is a general purpose data compression library. All the code is
7 thread safe. The data format used by the zlib library is described by RFCs
8 (Request for Comments) 1950 to 1952 in the files
9 http://www.ietf.org/rfc/rfc1950.txt (zlib format), rfc1951.txt (deflate format)
10 and rfc1952.txt (gzip format). These documents are also available in other
11 formats from ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html
13 All functions of the compression library are documented in the file zlib.h
14 (volunteer to write man pages welcome, contact zlib@gzip.org). A usage example
15 of the library is given in the file example.c which also tests that the library
16 is working correctly. Another example is given in the file minigzip.c. The
17 compression library itself is composed of all source files except example.c and
20 To compile all files and run the test program, follow the instructions given at
21 the top of Makefile. In short "make test; make install" should work for most
22 machines. For Unix: "./configure; make test; make install" For MSDOS, use one
23 of the special makefiles such as Makefile.msc. For VMS, use Make_vms.com or
26 Questions about zlib should be sent to <zlib@gzip.org>, or to Gilles Vollant
27 <info@winimage.com> for the Windows DLL version. The zlib home page is
28 http://www.zlib.org or http://www.gzip.org/zlib/ Before reporting a problem,
29 please check this site to verify that you have the latest version of zlib;
30 otherwise get the latest version and check whether the problem still exists or
33 PLEASE read the zlib FAQ http://www.gzip.org/zlib/zlib_faq.html before asking
36 Mark Nelson <markn@ieee.org> wrote an article about zlib for the Jan. 1997
37 issue of Dr. Dobb's Journal; a copy of the article is available in
38 http://dogma.net/markn/articles/zlibtool/zlibtool.htm
40 The changes made in version 1.2.1 are documented in the file ChangeLog.
42 Unsupported third party contributions are provided in directory "contrib".
44 A Java implementation of zlib is available in the Java Development Kit
45 http://java.sun.com/j2se/1.4.2/docs/api/java/util/zip/package-summary.html
46 See the zlib home page http://www.zlib.org for details.
48 A Perl interface to zlib written by Paul Marquess <pmqs@cpan.org> is in the
49 CPAN (Comprehensive Perl Archive Network) sites
50 http://www.cpan.org/modules/by-module/Compress/
52 A Python interface to zlib written by A.M. Kuchling <amk@magnet.com> is
53 available in Python 1.5 and later versions, see
54 http://www.python.org/doc/lib/module-zlib.html
56 A zlib binding for TCL written by Andreas Kupries <a.kupries@westend.com> is
57 availlable at http://www.oche.de/~akupries/soft/trf/trf_zip.html
59 An experimental package to read and write files in .zip format, written on top
60 of zlib by Gilles Vollant <info@winimage.com>, is available in the
61 contrib/minizip directory of zlib.
64 Notes for some targets:
66 - For Windows DLL versions, please see win32/DLL_FAQ.txt
68 - For 64-bit Irix, deflate.c must be compiled without any optimization. With
69 -O, one libpng test fails. The test works in 32 bit mode (with the -n32
70 compiler flag). The compiler bug has been reported to SGI.
72 - zlib doesn't work with gcc 2.6.3 on a DEC 3000/300LX under OSF/1 2.1 it works
73 when compiled with cc.
75 - On Digital Unix 4.0D (formely OSF/1) on AlphaServer, the cc option -std1 is
76 necessary to get gzprintf working correctly. This is done by configure.
78 - zlib doesn't work on HP-UX 9.05 with some versions of /bin/cc. It works with
79 other compilers. Use "make test" to check your compiler.
81 - gzdopen is not supported on RISCOS, BEOS and by some Mac compilers.
83 - For PalmOs, see http://palmzlib.sourceforge.net/
85 - When building a shared, i.e. dynamic library on Mac OS X, the library must be
86 installed before testing (do "make install" before "make test"), since the
87 library location is specified in the library.
92 The deflate format used by zlib was defined by Phil Katz. The deflate
93 and zlib specifications were written by L. Peter Deutsch. Thanks to all the
94 people who reported problems and suggested various improvements in zlib;
95 they are too numerous to cite here.
99 (C) 1995-2003 Jean-loup Gailly and Mark Adler
101 This software is provided 'as-is', without any express or implied
102 warranty. In no event will the authors be held liable for any damages
103 arising from the use of this software.
105 Permission is granted to anyone to use this software for any purpose,
106 including commercial applications, and to alter it and redistribute it
107 freely, subject to the following restrictions:
109 1. The origin of this software must not be misrepresented; you must not
110 claim that you wrote the original software. If you use this software
111 in a product, an acknowledgment in the product documentation would be
112 appreciated but is not required.
113 2. Altered source versions must be plainly marked as such, and must not be
114 misrepresented as being the original software.
115 3. This notice may not be removed or altered from any source distribution.
117 Jean-loup Gailly Mark Adler
118 jloup@gzip.org madler@alumni.caltech.edu
120 If you use the zlib library in a product, we would appreciate *not*
121 receiving lengthy legal documents to sign. The sources are provided
122 for free but without warranty of any kind. The library has been
123 entirely written by Jean-loup Gailly and Mark Adler; it does not
124 include third-party code.
126 If you redistribute modified sources, we would appreciate that you include
127 in the file ChangeLog history information documenting your changes. Please
128 read the FAQ for more information on the distribution of modified source