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ZLIB DATA COMPRESSION LIBRARY |
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zlib 1.2.8 is a general purpose data compression library. All the code is |
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thread safe. The data format used by the zlib library is described by RFCs |
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(Request for Comments) 1950 to 1952 in the files |
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http://tools.ietf.org/html/rfc1950 (zlib format), rfc1951 (deflate format) and |
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rfc1952 (gzip format). |
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All functions of the compression library are documented in the file zlib.h |
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(volunteer to write man pages welcome, contact zlib@gzip.org). A usage example |
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of the library is given in the file test/example.c which also tests that |
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the library is working correctly. Another example is given in the file |
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test/minigzip.c. The compression library itself is composed of all source |
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files in the root directory. |
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To compile all files and run the test program, follow the instructions given at |
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the top of Makefile.in. In short "./configure; make test", and if that goes |
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well, "make install" should work for most flavors of Unix. For Windows, use |
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one of the special makefiles in win32/ or contrib/vstudio/ . For VMS, use |
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make_vms.com. |
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Questions about zlib should be sent to <zlib@gzip.org>, or to Gilles Vollant |
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<info@winimage.com> for the Windows DLL version. The zlib home page is |
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http://zlib.net/ . Before reporting a problem, please check this site to |
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verify that you have the latest version of zlib; otherwise get the latest |
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version and check whether the problem still exists or not. |
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PLEASE read the zlib FAQ http://zlib.net/zlib_faq.html before asking for help. |
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Mark Nelson <markn@ieee.org> wrote an article about zlib for the Jan. 1997 |
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issue of Dr. Dobb's Journal; a copy of the article is available at |
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http://marknelson.us/1997/01/01/zlib-engine/ . |
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The changes made in version 1.2.8 are documented in the file ChangeLog. |
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Unsupported third party contributions are provided in directory contrib/ . |
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zlib is available in Java using the java.util.zip package, documented at |
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http://java.sun.com/developer/technicalArticles/Programming/compression/ . |
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A Perl interface to zlib written by Paul Marquess <pmqs@cpan.org> is available |
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at CPAN (Comprehensive Perl Archive Network) sites, including |
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http://search.cpan.org/~pmqs/IO-Compress-Zlib/ . |
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A Python interface to zlib written by A.M. Kuchling <amk@amk.ca> is |
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available in Python 1.5 and later versions, see |
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http://docs.python.org/library/zlib.html . |
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zlib is built into tcl: http://wiki.tcl.tk/4610 . |
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An experimental package to read and write files in .zip format, written on top |
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of zlib by Gilles Vollant <info@winimage.com>, is available in the |
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contrib/minizip directory of zlib. |
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Notes for some targets: |
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- For Windows DLL versions, please see win32/DLL_FAQ.txt |
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- For 64-bit Irix, deflate.c must be compiled without any optimization. With |
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-O, one libpng test fails. The test works in 32 bit mode (with the -n32 |
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compiler flag). The compiler bug has been reported to SGI. |
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|
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- zlib doesn't work with gcc 2.6.3 on a DEC 3000/300LX under OSF/1 2.1 it works |
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when compiled with cc. |
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- On Digital Unix 4.0D (formely OSF/1) on AlphaServer, the cc option -std1 is |
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necessary to get gzprintf working correctly. This is done by configure. |
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- zlib doesn't work on HP-UX 9.05 with some versions of /bin/cc. It works with |
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other compilers. Use "make test" to check your compiler. |
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- gzdopen is not supported on RISCOS or BEOS. |
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- For PalmOs, see http://palmzlib.sourceforge.net/ |
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Acknowledgments: |
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The deflate format used by zlib was defined by Phil Katz. The deflate and |
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zlib specifications were written by L. Peter Deutsch. Thanks to all the |
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people who reported problems and suggested various improvements in zlib; they |
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are too numerous to cite here. |
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Copyright notice: |
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(C) 1995-2013 Jean-loup Gailly and Mark Adler |
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This software is provided 'as-is', without any express or implied |
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warranty. In no event will the authors be held liable for any damages |
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arising from the use of this software. |
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Permission is granted to anyone to use this software for any purpose, |
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including commercial applications, and to alter it and redistribute it |
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freely, subject to the following restrictions: |
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1. The origin of this software must not be misrepresented; you must not |
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claim that you wrote the original software. If you use this software |
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in a product, an acknowledgment in the product documentation would be |
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appreciated but is not required. |
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2. Altered source versions must be plainly marked as such, and must not be |
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misrepresented as being the original software. |
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3. This notice may not be removed or altered from any source distribution. |
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|
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Jean-loup Gailly Mark Adler |
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jloup@gzip.org madler@alumni.caltech.edu |
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If you use the zlib library in a product, we would appreciate *not* receiving |
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lengthy legal documents to sign. The sources are provided for free but without |
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warranty of any kind. The library has been entirely written by Jean-loup |
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Gailly and Mark Adler; it does not include third-party code. |
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If you redistribute modified sources, we would appreciate that you include in |
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the file ChangeLog history information documenting your changes. Please read |
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the FAQ for more information on the distribution of modified source versions. |