1zlib 1.0.4 is a general purpose data compression library. All the code
2is reentrant (thread safe). The data format used by the zlib library
| 1zlib 1.1.1 is a general purpose data compression library. All the code
2is thread safe. The data format used by the zlib library
|
3is described by RFCs (Request for Comments) 1950 to 1952 in the files
4ftp://ds.internic.net/rfc/rfc1950.txt (zlib format), rfc1951.txt (deflate
5format) and rfc1952.txt (gzip format). These documents are also available in
6other formats from ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html
7
| 3is described by RFCs (Request for Comments) 1950 to 1952 in the files
4ftp://ds.internic.net/rfc/rfc1950.txt (zlib format), rfc1951.txt (deflate
5format) and rfc1952.txt (gzip format). These documents are also available in
6other formats from ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html
7
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8All functions of the compression library are documented in the file
9zlib.h. A usage example of the library is given in the file example.c
10which also tests that the library is working correctly. Another
11example is given in the file minigzip.c. The compression library itself
12is composed of all source files except example.c and minigzip.c.
| 8All functions of the compression library are documented in the file zlib.h
9(volunteer to write man pages welcome, contact jloup@gzip.org). A usage
10example of the library is given in the file example.c which also tests that
11the library is working correctly. Another example is given in the file
12minigzip.c. The compression library itself is composed of all source files
13except example.c and minigzip.c.
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13
14To compile all files and run the test program, follow the instructions
15given at the top of Makefile. In short "make test; make install"
16should work for most machines. For MSDOS, use one of the special
17makefiles such as Makefile.msc; for VMS, use Make_vms.com or descrip.mms.
18
19Questions about zlib should be sent to <zlib@quest.jpl.nasa.gov> or,
20if this fails, to the addresses given below in the Copyright section.
| 14
15To compile all files and run the test program, follow the instructions
16given at the top of Makefile. In short "make test; make install"
17should work for most machines. For MSDOS, use one of the special
18makefiles such as Makefile.msc; for VMS, use Make_vms.com or descrip.mms.
19
20Questions about zlib should be sent to <zlib@quest.jpl.nasa.gov> or,
21if this fails, to the addresses given below in the Copyright section.
|
21The zlib home page is http://quest.jpl.nasa.gov/zlib/
| 22The zlib home page is http://www.cdrom.com/pub/infozip/zlib/
23The official zlib ftp site is ftp://ftp.cdrom.com/pub/infozip/zlib/
24Mark Nelson wrote an article about zlib for the Jan. 1997 issue of
25Dr. Dobb's Journal; a copy of the article is available in
26http://web2.airmail.net/markn/articles/zlibtool/zlibtool.htm
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22
| 27
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23The changes made in version 1.0.4 are documented in the file ChangeLog.
24The main changes since 1.0.3 are:
| 28The changes made in version 1.1.1 are documented in the file ChangeLog.
29The main changes since 1.1.0 are:
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25
| 30
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26- In very rare conditions, deflate(s, Z_FINISH) could fail to produce an EOF
27 bit, so the decompressor could decompress all the correct data but went
28 on to attempt decompressing extra garbage data. This affected minigzip too.
29- zlibVersion and gzerror return const char* (needed for DLL)
30- port to RISCOS (no fdopen, no multiple dots, no unlink, no fileno)
| 31- fix macros _tr_tally_* in deflate.h for debug mode (Glenn Randers-Pehrson)
32- remove block truncation heuristic which had very marginal effect for zlib
33 (smaller lit_bufsize than in gzip 1.2.4) and degraded a little the
34 compression ratio on some files. This also allows inlining _tr_tally for
35 matches in deflate_slow.
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31
32
| 36
37
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| 38Unsupported third party contributions are provided in directory "contrib".
39
40A Java implementation of zlib is available in the Java Development Kit 1.1
41http://www.javasoft.com/products/JDK/1.1/docs/api/Package-java.util.zip.html
42See the zlib home page http://www.cdrom.com/pub/infozip/zlib/ for details.
43
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33A Perl interface to zlib written by Paul Marquess <pmarquess@bfsec.bt.co.uk>
34is in the CPAN (Comprehensive Perl Archive Network) sites, such as:
35ftp://ftp.cis.ufl.edu/pub/perl/CPAN/modules/by-module/Compress/Compress-Zlib*
36
| 44A Perl interface to zlib written by Paul Marquess <pmarquess@bfsec.bt.co.uk>
45is in the CPAN (Comprehensive Perl Archive Network) sites, such as:
46ftp://ftp.cis.ufl.edu/pub/perl/CPAN/modules/by-module/Compress/Compress-Zlib*
47
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| 48A Python interface to zlib written by A.M. Kuchling <amk@magnet.com>
49is available from the Python Software Association sites, such as:
50ftp://ftp.python.org/pub/python/contrib/Encoding/zlib*.tar.gz
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37
| 51
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| 52An experimental package to read files in .zip format, written on top of
53zlib by Gilles Vollant <info@winimage.com>, is available at
54http://www.winimage.com/zLibDll/unzip.html
55
56
|
38Notes for some targets:
39
| 57Notes for some targets:
58
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40- For Turbo C the small model is supported only with reduced performance to
41 avoid any far allocation; it was tested with -DMAX_WBITS=11 -DMAX_MEM_LEVEL=3
| 59- To build a Windows DLL version, include in a DLL project zlib.def, zlib.rc
60 and all .c files except example.c and minigzip.c; compile with -DZLIB_DLL
61 The zlib DLL support was initially done by Alessandro Iacopetti and is
62 now maintained by Gilles Vollant <info@winimage.com>. Check the zlib DLL
63 home page at http://www.winimage.com/zLibDll
|
42
| 64
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43- For 64-bit Iris, deflate.c must be compiled without any optimization.
| 65 From Visual Basic, you can call the DLL functions which do not take
66 a structure as argument: compress, uncompress and all gz* functions.
67 See contrib/visual-basic.txt for more information.
68 I don't know how to handle structures in Visual Basic, sorry.
69
70- For 64-bit Irix, deflate.c must be compiled without any optimization.
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44 With -O, one libpng test fails. The test works in 32 bit mode (with
| 71 With -O, one libpng test fails. The test works in 32 bit mode (with
|
45 the -32 compiler flag). The compiler bug has been reported to SGI.
| 72 the -n32 compiler flag). The compiler bug has been reported to SGI.
|
46
47- zlib doesn't work with gcc 2.6.3 on a DEC 3000/300LX under OSF/1 2.1
48 it works when compiled with cc.
49
| 73
74- zlib doesn't work with gcc 2.6.3 on a DEC 3000/300LX under OSF/1 2.1
75 it works when compiled with cc.
76
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50- zlib doesn't work on HP-UX 9.05 with one cc compiler (the one not
51 accepting the -O option). It works with the other cc compiler.
| 77- zlib doesn't work on HP-UX 9.05 with some versions of /bin/cc. It works
78 with other compilers. Use "make test" to check your compiler.
|
52
| 79
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53- To build a Windows DLL version, include in a DLL project zlib.def, zlib.rc
54 and all .c files except example.c and minigzip.c; compile with -DZLIB_DLL
55 For help on building a zlib DLL, contact Alessandro Iacopetti
56 <iaco@email.alessandria.alpcom.it> http://lisa.unial.it/iaco ,
57 or contact Brad Clarke <bclarke@cyberus.ca>.
| 80- For shared memory multiprocessors, the decompression code assumes that
81 writes to pointers are atomic. Also the functions zalloc and zfree passed
82 to deflateInit must be multi-threaded in this case.
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58
| 83
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59- gzdopen is not supported on RISCOS
| 84- gzdopen is not supported on RISCOS, BEOS and by some Mac compilers.
|
60
| 85
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| 86- For Turbo C the small model is supported only with reduced performance to
87 avoid any far allocation; it was tested with -DMAX_WBITS=11 -DMAX_MEM_LEVEL=3
|
61
| 88
|
| 89
|
62Acknowledgments:
63
64 The deflate format used by zlib was defined by Phil Katz. The deflate
65 and zlib specifications were written by Peter Deutsch. Thanks to all the
66 people who reported problems and suggested various improvements in zlib;
67 they are too numerous to cite here.
68
69Copyright notice:
70
| 90Acknowledgments:
91
92 The deflate format used by zlib was defined by Phil Katz. The deflate
93 and zlib specifications were written by Peter Deutsch. Thanks to all the
94 people who reported problems and suggested various improvements in zlib;
95 they are too numerous to cite here.
96
97Copyright notice:
98
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71 (C) 1995-1996 Jean-loup Gailly and Mark Adler
| 99 (C) 1995-1998 Jean-loup Gailly and Mark Adler
|
72
73 This software is provided 'as-is', without any express or implied
74 warranty. In no event will the authors be held liable for any damages
75 arising from the use of this software.
76
77 Permission is granted to anyone to use this software for any purpose,
78 including commercial applications, and to alter it and redistribute it
79 freely, subject to the following restrictions:
80
81 1. The origin of this software must not be misrepresented; you must not
82 claim that you wrote the original software. If you use this software
83 in a product, an acknowledgment in the product documentation would be
84 appreciated but is not required.
85 2. Altered source versions must be plainly marked as such, and must not be
86 misrepresented as being the original software.
87 3. This notice may not be removed or altered from any source distribution.
88
89 Jean-loup Gailly Mark Adler
| 100
101 This software is provided 'as-is', without any express or implied
102 warranty. In no event will the authors be held liable for any damages
103 arising from the use of this software.
104
105 Permission is granted to anyone to use this software for any purpose,
106 including commercial applications, and to alter it and redistribute it
107 freely, subject to the following restrictions:
108
109 1. The origin of this software must not be misrepresented; you must not
110 claim that you wrote the original software. If you use this software
111 in a product, an acknowledgment in the product documentation would be
112 appreciated but is not required.
113 2. Altered source versions must be plainly marked as such, and must not be
114 misrepresented as being the original software.
115 3. This notice may not be removed or altered from any source distribution.
116
117 Jean-loup Gailly Mark Adler
|
90 gzip@prep.ai.mit.edu madler@alumni.caltech.edu
| 118 jloup@gzip.org madler@alumni.caltech.edu
|
91
92If you use the zlib library in a product, we would appreciate *not*
93receiving lengthy legal documents to sign. The sources are provided
94for free but without warranty of any kind. The library has been
95entirely written by Jean-loup Gailly and Mark Adler; it does not
96include third-party code.
97
98If you redistribute modified sources, we would appreciate that you include
99in the file ChangeLog history information documenting your changes.
| 119
120If you use the zlib library in a product, we would appreciate *not*
121receiving lengthy legal documents to sign. The sources are provided
122for free but without warranty of any kind. The library has been
123entirely written by Jean-loup Gailly and Mark Adler; it does not
124include third-party code.
125
126If you redistribute modified sources, we would appreciate that you include
127in the file ChangeLog history information documenting your changes.
|