| 1 | ZLIB DATA COMPRESSION LIBRARY |
| 2 | |
| 3 | zlib 1.2.3 is a general purpose data compression library. All the code is |
| 4 | thread safe. The data format used by the zlib library is described by RFCs |
| 5 | (Request for Comments) 1950 to 1952 in the files |
| 6 | http://www.ietf.org/rfc/rfc1950.txt (zlib format), rfc1951.txt (deflate format) |
| 7 | and rfc1952.txt (gzip format). These documents are also available in other |
| 8 | formats from ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html |
| 9 | |
| 10 | All functions of the compression library are documented in the file zlib.h |
| 11 | (volunteer to write man pages welcome, contact zlib@gzip.org). A usage example |
| 12 | of the library is given in the file example.c which also tests that the library |
| 13 | is working correctly. Another example is given in the file minigzip.c. The |
| 14 | compression library itself is composed of all source files except example.c and |
| 15 | minigzip.c. |
| 16 | |
| 17 | To compile all files and run the test program, follow the instructions given at |
| 18 | the top of Makefile. In short "make test; make install" should work for most |
| 19 | machines. For Unix: "./configure; make test; make install". For MSDOS, use one |
| 20 | of the special makefiles such as Makefile.msc. For VMS, use make_vms.com. |
| 21 | |
| 22 | Questions about zlib should be sent to <zlib@gzip.org>, or to Gilles Vollant |
| 23 | <info@winimage.com> for the Windows DLL version. The zlib home page is |
| 24 | http://www.zlib.org or http://www.gzip.org/zlib/ Before reporting a problem, |
| 25 | please check this site to verify that you have the latest version of zlib; |
| 26 | otherwise get the latest version and check whether the problem still exists or |
| 27 | not. |
| 28 | |
| 29 | PLEASE read the zlib FAQ http://www.gzip.org/zlib/zlib_faq.html before asking |
| 30 | for help. |
| 31 | |
| 32 | Mark Nelson <markn@ieee.org> wrote an article about zlib for the Jan. 1997 |
| 33 | issue of Dr. Dobb's Journal; a copy of the article is available in |
| 34 | http://dogma.net/markn/articles/zlibtool/zlibtool.htm |
| 35 | |
| 36 | The changes made in version 1.2.3 are documented in the file ChangeLog. |
| 37 | |
| 38 | Unsupported third party contributions are provided in directory "contrib". |
| 39 | |
| 40 | A Java implementation of zlib is available in the Java Development Kit |
| 41 | http://java.sun.com/j2se/1.4.2/docs/api/java/util/zip/package-summary.html |
| 42 | See the zlib home page http://www.zlib.org for details. |
| 43 | |
| 44 | A Perl interface to zlib written by Paul Marquess <pmqs@cpan.org> is in the |
| 45 | CPAN (Comprehensive Perl Archive Network) sites |
| 46 | http://www.cpan.org/modules/by-module/Compress/ |
| 47 | |
| 48 | A Python interface to zlib written by A.M. Kuchling <amk@amk.ca> is |
| 49 | available in Python 1.5 and later versions, see |
| 50 | http://www.python.org/doc/lib/module-zlib.html |
| 51 | |
| 52 | A zlib binding for TCL written by Andreas Kupries <a.kupries@westend.com> is |
| 53 | availlable at http://www.oche.de/~akupries/soft/trf/trf_zip.html |
| 54 | |
| 55 | An experimental package to read and write files in .zip format, written on top |
| 56 | of zlib by Gilles Vollant <info@winimage.com>, is available in the |
| 57 | contrib/minizip directory of zlib. |
| 58 | |
| 59 | |
| 60 | Notes for some targets: |
| 61 | |
| 62 | - For Windows DLL versions, please see win32/DLL_FAQ.txt |
| 63 | |
| 64 | - For 64-bit Irix, deflate.c must be compiled without any optimization. With |
| 65 | -O, one libpng test fails. The test works in 32 bit mode (with the -n32 |
| 66 | compiler flag). The compiler bug has been reported to SGI. |
| 67 | |
| 68 | - zlib doesn't work with gcc 2.6.3 on a DEC 3000/300LX under OSF/1 2.1 it works |
| 69 | when compiled with cc. |
| 70 | |
| 71 | - On Digital Unix 4.0D (formely OSF/1) on AlphaServer, the cc option -std1 is |
| 72 | necessary to get gzprintf working correctly. This is done by configure. |
| 73 | |
| 74 | - zlib doesn't work on HP-UX 9.05 with some versions of /bin/cc. It works with |
| 75 | other compilers. Use "make test" to check your compiler. |
| 76 | |
| 77 | - gzdopen is not supported on RISCOS, BEOS and by some Mac compilers. |
| 78 | |
| 79 | - For PalmOs, see http://palmzlib.sourceforge.net/ |
| 80 | |
| 81 | - When building a shared, i.e. dynamic library on Mac OS X, the library must be |
| 82 | installed before testing (do "make install" before "make test"), since the |
| 83 | library location is specified in the library. |
| 84 | |
| 85 | |
| 86 | Acknowledgments: |
| 87 | |
| 88 | The deflate format used by zlib was defined by Phil Katz. The deflate |
| 89 | and zlib specifications were written by L. Peter Deutsch. Thanks to all the |
| 90 | people who reported problems and suggested various improvements in zlib; |
| 91 | they are too numerous to cite here. |
| 92 | |
| 93 | Copyright notice: |
| 94 | |
| 95 | (C) 1995-2004 Jean-loup Gailly and Mark Adler |
| 96 | |
| 97 | This software is provided 'as-is', without any express or implied |
| 98 | warranty. In no event will the authors be held liable for any damages |
| 99 | arising from the use of this software. |
| 100 | |
| 101 | Permission is granted to anyone to use this software for any purpose, |
| 102 | including commercial applications, and to alter it and redistribute it |
| 103 | freely, subject to the following restrictions: |
| 104 | |
| 105 | 1. The origin of this software must not be misrepresented; you must not |
| 106 | claim that you wrote the original software. If you use this software |
| 107 | in a product, an acknowledgment in the product documentation would be |
| 108 | appreciated but is not required. |
| 109 | 2. Altered source versions must be plainly marked as such, and must not be |
| 110 | misrepresented as being the original software. |
| 111 | 3. This notice may not be removed or altered from any source distribution. |
| 112 | |
| 113 | Jean-loup Gailly Mark Adler |
| 114 | jloup@gzip.org madler@alumni.caltech.edu |
| 115 | |
| 116 | If you use the zlib library in a product, we would appreciate *not* |
| 117 | receiving lengthy legal documents to sign. The sources are provided |
| 118 | for free but without warranty of any kind. The library has been |
| 119 | entirely written by Jean-loup Gailly and Mark Adler; it does not |
| 120 | include third-party code. |
| 121 | |
| 122 | If you redistribute modified sources, we would appreciate that you include |
| 123 | in the file ChangeLog history information documenting your changes. Please |
| 124 | read the FAQ for more information on the distribution of modified source |
| 125 | versions. |