| zlib 1.1.2 is a general purpose data compression library. All the code |
| is thread safe. The data format used by the zlib library |
| is described by RFCs (Request for Comments) 1950 to 1952 in the files |
| ftp://ds.internic.net/rfc/rfc1950.txt (zlib format), rfc1951.txt (deflate |
| format) and rfc1952.txt (gzip format). These documents are also available in |
| other formats from ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html |
| |
| All functions of the compression library are documented in the file zlib.h |
| (volunteer to write man pages welcome, contact jloup@gzip.org). A usage |
| example of the library is given in the file example.c which also tests that |
| the library is working correctly. Another example is given in the file |
| minigzip.c. The compression library itself is composed of all source files |
| except example.c and minigzip.c. |
| |
| To compile all files and run the test program, follow the instructions |
| given at the top of Makefile. In short "make test; make install" |
| should work for most machines. For MSDOS, use one of the special |
| makefiles such as Makefile.msc; for VMS, use Make_vms.com or descrip.mms. |
| |
| Questions about zlib should be sent to <zlib@quest.jpl.nasa.gov> or, |
| if this fails, to the addresses given below in the Copyright section. |
| The zlib home page is http://www.cdrom.com/pub/infozip/zlib/ |
| The official zlib ftp site is ftp://ftp.cdrom.com/pub/infozip/zlib/ |
| Mark Nelson <markn@tiny.com> wrote an article about zlib for the Jan. 1997 |
| issue of Dr. Dobb's Journal; a copy of the article is available in |
| http://web2.airmail.net/markn/articles/zlibtool/zlibtool.htm |
| |
| The changes made in version 1.1.2 are documented in the file ChangeLog. |
| The main changes since 1.1.1 are: |
| |
| - added contrib/minzip, mini zip and unzip based on zlib (Gilles Vollant) |
| See http://www.winimage.com/zLibDll/unzip.html |
| - preinitialize the inflate tables for fixed codes, to make the code |
| completely thread safe (Mark) |
| - some simplifications and slight speed-up to the inflate code (Mark) |
| - fix gzeof on non-compressed files (Allan Schrum) |
| - add -std1 option in configure for OSF1 to fix gzprintf (Martin Mokrejs) |
| - use default value of 4K for Z_BUFSIZE for 16-bit MSDOS (Tim Wegner + Glenn) |
| - added os2/Makefile.def and os2/zlib.def (Andrew Zabolotny) |
| - add shared lib support for UNIX_SV4.2MP (MATSUURA Takanori) |
| - do not wrap extern "C" around system includes (Tom Lane) |
| - added amiga/Makefile.pup for Amiga powerUP SAS/C PPC (Andreas Kleinert) |
| - allow "make install prefix=..." even after configure (Glenn Randers-Pehrson) |
| - allow "configure --prefix $HOME" (Tim Mooney) |
| |
| |
| Unsupported third party contributions are provided in directory "contrib". |
| |
| A Java implementation of zlib is available in the Java Development Kit 1.1 |
| http://www.javasoft.com/products/JDK/1.1/docs/api/Package-java.util.zip.html |
| See the zlib home page http://www.cdrom.com/pub/infozip/zlib/ for details. |
| |
| A Perl interface to zlib written by Paul Marquess <pmarquess@bfsec.bt.co.uk> |
| is in the CPAN (Comprehensive Perl Archive Network) sites, such as: |
| ftp://ftp.cis.ufl.edu/pub/perl/CPAN/modules/by-module/Compress/Compress-Zlib* |
| |
| A Python interface to zlib written by A.M. Kuchling <amk@magnet.com> |
| is available from the Python Software Association sites, such as: |
| ftp://ftp.python.org/pub/python/contrib/Encoding/zlib*.tar.gz |
| |
| A zlib binding for TCL written by Andreas Kupries <a.kupries@westend.com> |
| is availlable at http://www.westend.com/~kupries/doc/trf/man/man.html |
| |
| An experimental package to read and write files in .zip format, |
| written on top of zlib by Gilles Vollant <info@winimage.com>, is |
| available at http://www.winimage.com/zLibDll/unzip.html |
| and also in the contrib/minizip directory of zlib. |
| |
| |
| Notes for some targets: |
| |
| - To build a Windows DLL version, include in a DLL project zlib.def, zlib.rc |
| and all .c files except example.c and minigzip.c; compile with -DZLIB_DLL |
| The zlib DLL support was initially done by Alessandro Iacopetti and is |
| now maintained by Gilles Vollant <info@winimage.com>. Check the zlib DLL |
| home page at http://www.winimage.com/zLibDll |
| |
| From Visual Basic, you can call the DLL functions which do not take |
| a structure as argument: compress, uncompress and all gz* functions. |
| See contrib/visual-basic.txt for more information. |
| I don't know how to handle structures in Visual Basic, sorry. |
| |
| - For 64-bit Irix, deflate.c must be compiled without any optimization. |
| With -O, one libpng test fails. The test works in 32 bit mode (with |
| the -n32 compiler flag). The compiler bug has been reported to SGI. |
| |
| - zlib doesn't work with gcc 2.6.3 on a DEC 3000/300LX under OSF/1 2.1 |
| it works when compiled with cc. |
| |
| - on Digital Unix 4.0D (formely OSF/1) on AlphaServer, the cc option -std1 |
| is necessary to get gzprintf working correctly. This is done by configure. |
| |
| - zlib doesn't work on HP-UX 9.05 with some versions of /bin/cc. It works |
| with other compilers. Use "make test" to check your compiler. |
| |
| - For shared memory multiprocessors, the decompression code assumes that |
| writes to pointers are atomic. Also the functions zalloc and zfree passed |
| to deflateInit must be multi-threaded in this case. |
| |
| - gzdopen is not supported on RISCOS, BEOS and by some Mac compilers. |
| |
| - For Turbo C the small model is supported only with reduced performance to |
| avoid any far allocation; it was tested with -DMAX_WBITS=11 -DMAX_MEM_LEVEL=3 |
| |
| |
| Acknowledgments: |
| |
| 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; |
| they are too numerous to cite here. |
| |
| Copyright notice: |
| |
| (C) 1995-1998 Jean-loup Gailly and Mark Adler |
| |
| This software is provided 'as-is', without any express or implied |
| warranty. 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 distribution. |
| |
| Jean-loup Gailly Mark Adler |
| jloup@gzip.org madler@alumni.caltech.edu |
| |
| If you use the zlib library in a product, we would appreciate *not* |
| receiving lengthy legal documents to sign. The sources are provided |
| for free but without warranty of any kind. The library has been |
| entirely written by Jean-loup Gailly and Mark Adler; it does not |
| include third-party code. |
| |
| If you redistribute modified sources, we would appreciate that you include |
| in the file ChangeLog history information documenting your changes. |
