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1*22ce4affSfengbojiangZLIB DATA COMPRESSION LIBRARY
2*22ce4affSfengbojiang
3*22ce4affSfengbojiangzlib 1.2.11 is a general purpose data compression library.  All the code is
4*22ce4affSfengbojiangthread safe.  The data format used by the zlib library is described by RFCs
5*22ce4affSfengbojiang(Request for Comments) 1950 to 1952 in the files
6*22ce4affSfengbojianghttp://tools.ietf.org/html/rfc1950 (zlib format), rfc1951 (deflate format) and
7*22ce4affSfengbojiangrfc1952 (gzip format).
8*22ce4affSfengbojiang
9*22ce4affSfengbojiangAll functions of the compression library are documented in the file zlib.h
10*22ce4affSfengbojiang(volunteer to write man pages welcome, contact [email protected]).  A usage example
11*22ce4affSfengbojiangof the library is given in the file test/example.c which also tests that
12*22ce4affSfengbojiangthe library is working correctly.  Another example is given in the file
13*22ce4affSfengbojiangtest/minigzip.c.  The compression library itself is composed of all source
14*22ce4affSfengbojiangfiles in the root directory.
15*22ce4affSfengbojiang
16*22ce4affSfengbojiangTo compile all files and run the test program, follow the instructions given at
17*22ce4affSfengbojiangthe top of Makefile.in.  In short "./configure; make test", and if that goes
18*22ce4affSfengbojiangwell, "make install" should work for most flavors of Unix.  For Windows, use
19*22ce4affSfengbojiangone of the special makefiles in win32/ or contrib/vstudio/ .  For VMS, use
20*22ce4affSfengbojiangmake_vms.com.
21*22ce4affSfengbojiang
22*22ce4affSfengbojiangQuestions about zlib should be sent to <[email protected]>, or to Gilles Vollant
23*22ce4affSfengbojiang<[email protected]> for the Windows DLL version.  The zlib home page is
24*22ce4affSfengbojianghttp://zlib.net/ .  Before reporting a problem, please check this site to
25*22ce4affSfengbojiangverify that you have the latest version of zlib; otherwise get the latest
26*22ce4affSfengbojiangversion and check whether the problem still exists or not.
27*22ce4affSfengbojiang
28*22ce4affSfengbojiangPLEASE read the zlib FAQ http://zlib.net/zlib_faq.html before asking for help.
29*22ce4affSfengbojiang
30*22ce4affSfengbojiangMark Nelson <[email protected]> wrote an article about zlib for the Jan.  1997
31*22ce4affSfengbojiangissue of Dr.  Dobb's Journal; a copy of the article is available at
32*22ce4affSfengbojianghttp://marknelson.us/1997/01/01/zlib-engine/ .
33*22ce4affSfengbojiang
34*22ce4affSfengbojiangThe changes made in version 1.2.11 are documented in the file ChangeLog.
35*22ce4affSfengbojiang
36*22ce4affSfengbojiangUnsupported third party contributions are provided in directory contrib/ .
37*22ce4affSfengbojiang
38*22ce4affSfengbojiangzlib is available in Java using the java.util.zip package, documented at
39*22ce4affSfengbojianghttp://java.sun.com/developer/technicalArticles/Programming/compression/ .
40*22ce4affSfengbojiang
41*22ce4affSfengbojiangA Perl interface to zlib written by Paul Marquess <[email protected]> is available
42*22ce4affSfengbojiangat CPAN (Comprehensive Perl Archive Network) sites, including
43*22ce4affSfengbojianghttp://search.cpan.org/~pmqs/IO-Compress-Zlib/ .
44*22ce4affSfengbojiang
45*22ce4affSfengbojiangA Python interface to zlib written by A.M. Kuchling <[email protected]> is
46*22ce4affSfengbojiangavailable in Python 1.5 and later versions, see
47*22ce4affSfengbojianghttp://docs.python.org/library/zlib.html .
48*22ce4affSfengbojiang
49*22ce4affSfengbojiangzlib is built into tcl: http://wiki.tcl.tk/4610 .
50*22ce4affSfengbojiang
51*22ce4affSfengbojiangAn experimental package to read and write files in .zip format, written on top
52*22ce4affSfengbojiangof zlib by Gilles Vollant <[email protected]>, is available in the
53*22ce4affSfengbojiangcontrib/minizip directory of zlib.
54*22ce4affSfengbojiang
55*22ce4affSfengbojiang
56*22ce4affSfengbojiangNotes for some targets:
57*22ce4affSfengbojiang
58*22ce4affSfengbojiang- For Windows DLL versions, please see win32/DLL_FAQ.txt
59*22ce4affSfengbojiang
60*22ce4affSfengbojiang- For 64-bit Irix, deflate.c must be compiled without any optimization. With
61*22ce4affSfengbojiang  -O, one libpng test fails. The test works in 32 bit mode (with the -n32
62*22ce4affSfengbojiang  compiler flag). The compiler bug has been reported to SGI.
63*22ce4affSfengbojiang
64*22ce4affSfengbojiang- zlib doesn't work with gcc 2.6.3 on a DEC 3000/300LX under OSF/1 2.1 it works
65*22ce4affSfengbojiang  when compiled with cc.
66*22ce4affSfengbojiang
67*22ce4affSfengbojiang- On Digital Unix 4.0D (formely OSF/1) on AlphaServer, the cc option -std1 is
68*22ce4affSfengbojiang  necessary to get gzprintf working correctly. This is done by configure.
69*22ce4affSfengbojiang
70*22ce4affSfengbojiang- zlib doesn't work on HP-UX 9.05 with some versions of /bin/cc. It works with
71*22ce4affSfengbojiang  other compilers. Use "make test" to check your compiler.
72*22ce4affSfengbojiang
73*22ce4affSfengbojiang- gzdopen is not supported on RISCOS or BEOS.
74*22ce4affSfengbojiang
75*22ce4affSfengbojiang- For PalmOs, see http://palmzlib.sourceforge.net/
76*22ce4affSfengbojiang
77*22ce4affSfengbojiang
78*22ce4affSfengbojiangAcknowledgments:
79*22ce4affSfengbojiang
80*22ce4affSfengbojiang  The deflate format used by zlib was defined by Phil Katz.  The deflate and
81*22ce4affSfengbojiang  zlib specifications were written by L.  Peter Deutsch.  Thanks to all the
82*22ce4affSfengbojiang  people who reported problems and suggested various improvements in zlib; they
83*22ce4affSfengbojiang  are too numerous to cite here.
84*22ce4affSfengbojiang
85*22ce4affSfengbojiangCopyright notice:
86*22ce4affSfengbojiang
87*22ce4affSfengbojiang (C) 1995-2017 Jean-loup Gailly and Mark Adler
88*22ce4affSfengbojiang
89*22ce4affSfengbojiang  This software is provided 'as-is', without any express or implied
90*22ce4affSfengbojiang  warranty.  In no event will the authors be held liable for any damages
91*22ce4affSfengbojiang  arising from the use of this software.
92*22ce4affSfengbojiang
93*22ce4affSfengbojiang  Permission is granted to anyone to use this software for any purpose,
94*22ce4affSfengbojiang  including commercial applications, and to alter it and redistribute it
95*22ce4affSfengbojiang  freely, subject to the following restrictions:
96*22ce4affSfengbojiang
97*22ce4affSfengbojiang  1. The origin of this software must not be misrepresented; you must not
98*22ce4affSfengbojiang     claim that you wrote the original software. If you use this software
99*22ce4affSfengbojiang     in a product, an acknowledgment in the product documentation would be
100*22ce4affSfengbojiang     appreciated but is not required.
101*22ce4affSfengbojiang  2. Altered source versions must be plainly marked as such, and must not be
102*22ce4affSfengbojiang     misrepresented as being the original software.
103*22ce4affSfengbojiang  3. This notice may not be removed or altered from any source distribution.
104*22ce4affSfengbojiang
105*22ce4affSfengbojiang  Jean-loup Gailly        Mark Adler
106*22ce4affSfengbojiang  [email protected]          [email protected]
107*22ce4affSfengbojiang
108*22ce4affSfengbojiangIf you use the zlib library in a product, we would appreciate *not* receiving
109*22ce4affSfengbojianglengthy legal documents to sign.  The sources are provided for free but without
110*22ce4affSfengbojiangwarranty of any kind.  The library has been entirely written by Jean-loup
111*22ce4affSfengbojiangGailly and Mark Adler; it does not include third-party code.
112*22ce4affSfengbojiang
113*22ce4affSfengbojiangIf you redistribute modified sources, we would appreciate that you include in
114*22ce4affSfengbojiangthe file ChangeLog history information documenting your changes.  Please read
115*22ce4affSfengbojiangthe FAQ for more information on the distribution of modified source versions.
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