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ZLIB(3)			   Library Functions Manual		       ZLIB(3)

NAME
       zlib - compression/decompression	library

SYNOPSIS
       [see zlib.h for full description]

DESCRIPTION
       The  zlib  library  is a	general	purpose	data compression library.  The
       code is thread safe, assuming that the standard library functions  used
       are  thread  safe, such as memory allocation routines.  It provides in-
       memory compression and  decompression  functions,  including  integrity
       checks  of the uncompressed data.  This version of the library supports
       only one	compression method (deflation) but  other  algorithms  may  be
       added later with	the same stream	interface.

       Compression  can	 be  done  in  a  single step if the buffers are large
       enough or can be	done by	repeated calls of  the	compression  function.
       In the latter case, the application must	provide	more input and/or con-
       sume the	output (providing more output space) before each call.

       The  library  also  supports reading and	writing	files in gzip(1) (.gz)
       format 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 the 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 in	the files test/example.c and test/minigzip.c, as well as other
       examples	in the examples/ directory.

       Changes to this version are documented in the file ChangeLog  that  ac-
       companies the source.

       zlib is built in	to many	languages and operating	systems, including but
       not limited to Java, Python, .NET, PHP, Perl, Ruby, Swift, and Go.

       An  experimental	 package  to  read and write files in the .zip format,
       written on top of zlib by Gilles	Vollant	(info@winimage.com), is	avail-
       able at:

	      http://www.winimage.com/zLibDll/minizip.html  and	 also  in  the
	      contrib/minizip directory	of the main zlib source	distribution.

SEE ALSO
       The zlib	web site can be	found at:

	      http://zlib.net/

       The  data  format used by the zlib library is described by RFC (Request
       for Comments) 1950 to 1952 in the files:

	      http://tools.ietf.org/html/rfc1950  (for	the  zlib  header  and
	      trailer format)
	      http://tools.ietf.org/html/rfc1951  (for	the deflate compressed
	      data format)
	      http://tools.ietf.org/html/rfc1952  (for	the  gzip  header  and
	      trailer format)

       Mark Nelson wrote an article about zlib for the Jan. 1997 issue of  Dr.
       Dobb's Journal; a copy of the article is	available at:

	      http://marknelson.us/1997/01/01/zlib-engine/

REPORTING PROBLEMS
       Before  reporting  a  problem, please check the zlib web	site to	verify
       that you	have the latest	version	of zlib; otherwise, obtain the	latest
       version	and see	if the problem still exists.  Please read the zlib FAQ
       at:

	      http://zlib.net/zlib_faq.html

       before  asking  for  help.    Send   questions	and/or	 comments   to
       zlib@gzip.org,  or  (for	 the  Windows  DLL  version) to	Gilles Vollant
       (info@winimage.com).

AUTHORS	AND LICENSE
       Version 1.3

       Copyright (C) 1995-2023 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.

       Permission is granted to	anyone to use this software for	 any  purpose,
       including  commercial applications, and to alter	it and redistribute it
       freely, subject to the following	restrictions:

       1. The origin of	this software must not be misrepresented; you must not
	  claim	that you wrote the original software. If you use this software
	  in a product,	an acknowledgment in the product  documentation	 would
	  be appreciated but is	not required.

       2. Altered source versions must be plainly marked as such, and must not
	  be misrepresented as being the original software.

       3. This	notice may not be removed or altered from any source distribu-
	  tion.

       Jean-loup Gailly	       Mark Adler
       jloup@gzip.org	       madler@alumni.caltech.edu

       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
       (rodgers@nlm.nih.gov).

				  18 Aug 2023			       ZLIB(3)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | REPORTING PROBLEMS | AUTHORS AND LICENSE

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