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.TH ZLIB 3 "28 Apr 2013" |
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.SH NAME |
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zlib \- compression/decompression library |
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.SH SYNOPSIS |
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[see |
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.I zlib.h |
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for full description] |
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.SH DESCRIPTION |
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The |
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.I zlib |
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library is a general purpose data compression library. |
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The code is thread safe, assuming that the standard library functions |
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used are thread safe, such as memory allocation routines. |
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It provides in-memory compression and decompression functions, |
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including integrity checks of the uncompressed data. |
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This version of the library supports only one compression method (deflation) |
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but other algorithms may be added later |
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with the same stream interface. |
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.LP |
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Compression can be done in a single step if the buffers are large enough |
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or can be done by repeated calls of the compression function. |
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In the latter case, |
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the application must provide more input and/or consume the output |
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(providing more output space) before each call. |
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.LP |
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The library also supports reading and writing files in |
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.IR gzip (1) |
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(.gz) format |
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with an interface similar to that of stdio. |
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.LP |
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The library does not install any signal handler. |
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The decoder checks the consistency of the compressed data, |
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so the library should never crash even in the case of corrupted input. |
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.LP |
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All functions of the compression library are documented in the file |
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.IR zlib.h . |
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The distribution source includes examples of use of the library |
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in the files |
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.I test/example.c |
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and |
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.IR test/minigzip.c, |
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as well as other examples in the |
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.IR examples/ |
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directory. |
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.LP |
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Changes to this version are documented in the file |
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.I ChangeLog |
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that accompanies the source. |
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.LP |
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.I zlib |
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is available in Java using the java.util.zip package: |
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.IP |
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http://java.sun.com/developer/technicalArticles/Programming/compression/ |
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.LP |
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A Perl interface to |
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.IR zlib , |
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written by Paul Marquess (pmqs@cpan.org), |
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is available at CPAN (Comprehensive Perl Archive Network) sites, |
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including: |
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.IP |
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http://search.cpan.org/~pmqs/IO-Compress-Zlib/ |
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.LP |
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A Python interface to |
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.IR zlib , |
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written by A.M. Kuchling (amk@magnet.com), |
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is available in Python 1.5 and later versions: |
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.IP |
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http://docs.python.org/library/zlib.html |
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.LP |
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.I zlib |
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is built into |
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.IR tcl: |
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.IP |
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http://wiki.tcl.tk/4610 |
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.LP |
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An experimental package to read and write files in .zip format, |
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written on top of |
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.I zlib |
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by Gilles Vollant (info@winimage.com), |
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is available at: |
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.IP |
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http://www.winimage.com/zLibDll/minizip.html |
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and also in the |
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.I contrib/minizip |
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directory of the main |
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.I zlib |
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source distribution. |
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.SH "SEE ALSO" |
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The |
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.I zlib |
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web site can be found at: |
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.IP |
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http://zlib.net/ |
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.LP |
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The data format used by the zlib library is described by RFC |
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(Request for Comments) 1950 to 1952 in the files: |
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.IP |
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http://tools.ietf.org/html/rfc1950 (for the zlib header and trailer format) |
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.br |
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http://tools.ietf.org/html/rfc1951 (for the deflate compressed data format) |
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.br |
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http://tools.ietf.org/html/rfc1952 (for the gzip header and trailer format) |
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.LP |
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Mark Nelson wrote an article about |
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.I zlib |
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for the Jan. 1997 issue of Dr. Dobb's Journal; |
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a copy of the article is available at: |
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.IP |
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http://marknelson.us/1997/01/01/zlib-engine/ |
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.SH "REPORTING PROBLEMS" |
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Before reporting a problem, |
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please check the |
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.I zlib |
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web site to verify that you have the latest version of |
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.IR zlib ; |
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otherwise, |
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obtain the latest version and see if the problem still exists. |
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Please read the |
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.I zlib |
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FAQ at: |
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.IP |
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http://zlib.net/zlib_faq.html |
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.LP |
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before asking for help. |
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Send questions and/or comments to zlib@gzip.org, |
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or (for the Windows DLL version) to Gilles Vollant (info@winimage.com). |
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.SH AUTHORS |
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Version 1.2.8 |
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Copyright (C) 1995-2013 Jean-loup Gailly (jloup@gzip.org) |
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and Mark Adler (madler@alumni.caltech.edu). |
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.LP |
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This software is provided "as-is," |
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without any express or implied warranty. |
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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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See the distribution directory with respect to requirements |
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governing redistribution. |
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The deflate format used by |
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.I zlib |
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was defined by Phil Katz. |
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The deflate and |
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.I zlib |
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specifications were written by L. Peter Deutsch. |
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Thanks to all the people who reported problems and suggested various |
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improvements in |
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.IR zlib ; |
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who are too numerous to cite here. |
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.LP |
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UNIX manual page by R. P. C. Rodgers, |
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U.S. National Library of Medicine (rodgers@nlm.nih.gov). |
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.\" end of man page |