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ZLIB(3)			   Library Functions Manual		       ZLIB(3)

       zlib - compression/decompression	library

       [see zlib.h for full description]

       The  zlib  library  is a	general	purpose	data compression library.  The
       code is thread safe.  It	provides in-memory compression and  decompres-
       sion  functions,	 including  integrity checks of	the uncompressed data.
       This version of the library supports only one compression  method  (de-
       flation)	 but  other  algorithms	 will be added later and will have the
       same stream interface.

       Compression can be done in a single  step  if  the  buffers  are	 large
       enough (for example if an input file is mmap'ed), or can	be done	by re-
       peated calls of the compression function.  In the latter	case, the  ap-
       plication  must provide more input and/or consume the output (providing
       more output space) before each call.

       The library also	supports reading and writing files in gzip (.gz)  for-
       mat with	an interface similar to	that of	stdio.

       The  library  does  not install any signal handler.  The	decoder	checks
       the consistency of the compressed data, so  the	library	 should	 never
       crash even in case of corrupted input.

       All  functions  of  the	compression library are	documented in the file
       zlib.h.	The distribution source	includes examples of use  of  the  li-
       brary the files example.c and minigzip.c.

       A  Java implementation of zlib is available in the Java Development Kit

       A  Perl	interface  to  zlib,  written  by Paul Marquess	(pmarquess@bf- is	available at CPAN (Comprehensive Perl Archive Network)
       sites, such as:

       A Python	interface to zlib written by A.M. Kuchling <> is
       available from the Python Software Association sites, such as:*.tar.gz

       Questions about zlib should be sent to:  or,  if	this  fails, to	the author ad-
	      dresses given below.  The	zlib home page is:

       The data	format used by the zlib	library	is described by	 RFC  (Request
       for Comments) 1950 to 1952 in the files: (zlib format)
	      rfc1951.txt (deflate format)
	      rfc1952.txt (gzip	format)

       These documents are also	available in other formats from:

       Version 1.1.4 Copyright (C) 1995-2002 Jean-loup Gailly (
       and Mark	Adler (

       This software is	provided "as-is," without any express or implied  war-
       ranty.	In  no	event  will the	authors	be held	liable for any damages
       arising from the	use of this software.  See the distribution  directory
       with  respect  to  requirements	governing redistribution.  The deflate
       format used by zlib was defined by Phil Katz.   The  deflate  and  zlib
       specifications  were  written  by  L. Peter Deutsch.  Thanks to all the
       people who reported problems  and  suggested  various  improvements  in
       zlib; who are too numerous to cite here.

       UNIX manual page	by R. P. C. Rodgers, U.S. National Library of Medicine

				 11 March 2002			       ZLIB(3)


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