Python2/PyMuPDF: mupdf-source/thirdparty/zlib/FAQ annotate

annotate mupdf-source/thirdparty/zlib/FAQ @ 46:7ee69f120f19 default tip

>>>>> tag v1.26.5+1 for changeset b74429b0f5c4

author	Franz Glasner <fzglas.hg@dom66.de>
date	Sat, 11 Oct 2025 17:17:30 +0200
parents	b50eed0cc0ef
children

rev	line source
2 b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	1
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	2 Frequently Asked Questions about zlib
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	3
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	4
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	5 If your question is not there, please check the zlib home page
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	6 http://zlib.net/ which may have more recent information.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	7 The latest zlib FAQ is at http://zlib.net/zlib_faq.html
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	8
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	9
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	10 1. Is zlib Y2K-compliant?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	11
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	12 Yes. zlib doesn't handle dates.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	13
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	14 2. Where can I get a Windows DLL version?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	15
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	16 The zlib sources can be compiled without change to produce a DLL. See the
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	17 file win32/DLL_FAQ.txt in the zlib distribution.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	18
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	19 3. Where can I get a Visual Basic interface to zlib?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	20
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	21 See
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	22 * http://marknelson.us/1997/01/01/zlib-engine/
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	23 * win32/DLL_FAQ.txt in the zlib distribution
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	24
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	25 4. compress() returns Z_BUF_ERROR.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	26
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	27 Make sure that before the call of compress(), the length of the compressed
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	28 buffer is equal to the available size of the compressed buffer and not
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	29 zero. For Visual Basic, check that this parameter is passed by reference
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	30 ("as any"), not by value ("as long").
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	31
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	32 5. deflate() or inflate() returns Z_BUF_ERROR.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	33
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	34 Before making the call, make sure that avail_in and avail_out are not zero.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	35 When setting the parameter flush equal to Z_FINISH, also make sure that
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	36 avail_out is big enough to allow processing all pending input. Note that a
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	37 Z_BUF_ERROR is not fatal--another call to deflate() or inflate() can be
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	38 made with more input or output space. A Z_BUF_ERROR may in fact be
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	39 unavoidable depending on how the functions are used, since it is not
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	40 possible to tell whether or not there is more output pending when
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	41 strm.avail_out returns with zero. See http://zlib.net/zlib_how.html for a
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	42 heavily annotated example.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	43
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	44 6. Where's the zlib documentation (man pages, etc.)?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	45
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	46 It's in zlib.h . Examples of zlib usage are in the files test/example.c
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	47 and test/minigzip.c, with more in examples/ .
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	48
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	49 7. Why don't you use GNU autoconf or libtool or ...?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	50
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	51 Because we would like to keep zlib as a very small and simple package.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	52 zlib is rather portable and doesn't need much configuration.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	53
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	54 8. I found a bug in zlib.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	55
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	56 Most of the time, such problems are due to an incorrect usage of zlib.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	57 Please try to reproduce the problem with a small program and send the
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	58 corresponding source to us at zlib@gzip.org . Do not send multi-megabyte
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	59 data files without prior agreement.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	60
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	61 9. Why do I get "undefined reference to gzputc"?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	62
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	63 If "make test" produces something like
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	64
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	65 example.o(.text+0x154): undefined reference to `gzputc'
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	66
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	67 check that you don't have old files libz.* in /usr/lib, /usr/local/lib or
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	68 /usr/X11R6/lib. Remove any old versions, then do "make install".
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	69
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	70 10. I need a Delphi interface to zlib.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	71
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	72 See the contrib/delphi directory in the zlib distribution.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	73
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	74 11. Can zlib handle .zip archives?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	75
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	76 Not by itself, no. See the directory contrib/minizip in the zlib
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	77 distribution.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	78
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	79 12. Can zlib handle .Z files?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	80
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	81 No, sorry. You have to spawn an uncompress or gunzip subprocess, or adapt
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	82 the code of uncompress on your own.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	83
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	84 13. How can I make a Unix shared library?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	85
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	86 By default a shared (and a static) library is built for Unix. So:
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	87
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	88 make distclean
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	89 ./configure
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	90 make
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	91
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	92 14. How do I install a shared zlib library on Unix?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	93
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	94 After the above, then:
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	95
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	96 make install
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	97
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	98 However, many flavors of Unix come with a shared zlib already installed.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	99 Before going to the trouble of compiling a shared version of zlib and
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	100 trying to install it, you may want to check if it's already there! If you
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	101 can #include <zlib.h>, it's there. The -lz option will probably link to
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	102 it. You can check the version at the top of zlib.h or with the
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	103 ZLIB_VERSION symbol defined in zlib.h .
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	104
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	105 15. I have a question about OttoPDF.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	106
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	107 We are not the authors of OttoPDF. The real author is on the OttoPDF web
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	108 site: Joel Hainley, jhainley@myndkryme.com.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	109
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	110 16. Can zlib decode Flate data in an Adobe PDF file?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	111
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	112 Yes. See http://www.pdflib.com/ . To modify PDF forms, see
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	113 http://sourceforge.net/projects/acroformtool/ .
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	114
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	115 17. Why am I getting this "register_frame_info not found" error on Solaris?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	116
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	117 After installing zlib 1.1.4 on Solaris 2.6, running applications using zlib
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	118 generates an error such as:
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	119
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	120 ld.so.1: rpm: fatal: relocation error: file /usr/local/lib/libz.so:
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	121 symbol __register_frame_info: referenced symbol not found
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	122
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	123 The symbol __register_frame_info is not part of zlib, it is generated by
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	124 the C compiler (cc or gcc). You must recompile applications using zlib
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	125 which have this problem. This problem is specific to Solaris. See
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	126 http://www.sunfreeware.com for Solaris versions of zlib and applications
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	127 using zlib.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	128
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	129 18. Why does gzip give an error on a file I make with compress/deflate?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	130
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	131 The compress and deflate functions produce data in the zlib format, which
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	132 is different and incompatible with the gzip format. The gz* functions in
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	133 zlib on the other hand use the gzip format. Both the zlib and gzip formats
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	134 use the same compressed data format internally, but have different headers
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	135 and trailers around the compressed data.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	136
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	137 19. Ok, so why are there two different formats?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	138
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	139 The gzip format was designed to retain the directory information about a
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	140 single file, such as the name and last modification date. The zlib format
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	141 on the other hand was designed for in-memory and communication channel
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	142 applications, and has a much more compact header and trailer and uses a
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	143 faster integrity check than gzip.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	144
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	145 20. Well that's nice, but how do I make a gzip file in memory?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	146
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	147 You can request that deflate write the gzip format instead of the zlib
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	148 format using deflateInit2(). You can also request that inflate decode the
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	149 gzip format using inflateInit2(). Read zlib.h for more details.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	150
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	151 21. Is zlib thread-safe?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	152
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	153 Yes. However any library routines that zlib uses and any application-
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	154 provided memory allocation routines must also be thread-safe. zlib's gz*
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	155 functions use stdio library routines, and most of zlib's functions use the
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	156 library memory allocation routines by default. zlib's Init functions
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	157 allow for the application to provide custom memory allocation routines.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	158
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	159 Of course, you should only operate on any given zlib or gzip stream from a
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	160 single thread at a time.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	161
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	162 22. Can I use zlib in my commercial application?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	163
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	164 Yes. Please read the license in zlib.h.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	165
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	166 23. Is zlib under the GNU license?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	167
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	168 No. Please read the license in zlib.h.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	169
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	170 24. The license says that altered source versions must be "plainly marked". So
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	171 what exactly do I need to do to meet that requirement?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	172
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	173 You need to change the ZLIB_VERSION and ZLIB_VERNUM #defines in zlib.h. In
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	174 particular, the final version number needs to be changed to "f", and an
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	175 identification string should be appended to ZLIB_VERSION. Version numbers
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	176 x.x.x.f are reserved for modifications to zlib by others than the zlib
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	177 maintainers. For example, if the version of the base zlib you are altering
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	178 is "1.2.3.4", then in zlib.h you should change ZLIB_VERNUM to 0x123f, and
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	179 ZLIB_VERSION to something like "1.2.3.f-zachary-mods-v3". You can also
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	180 update the version strings in deflate.c and inftrees.c.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	181
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	182 For altered source distributions, you should also note the origin and
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	183 nature of the changes in zlib.h, as well as in ChangeLog and README, along
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	184 with the dates of the alterations. The origin should include at least your
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	185 name (or your company's name), and an email address to contact for help or
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	186 issues with the library.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	187
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	188 Note that distributing a compiled zlib library along with zlib.h and
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	189 zconf.h is also a source distribution, and so you should change
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	190 ZLIB_VERSION and ZLIB_VERNUM and note the origin and nature of the changes
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	191 in zlib.h as you would for a full source distribution.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	192
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	193 25. Will zlib work on a big-endian or little-endian architecture, and can I
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	194 exchange compressed data between them?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	195
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	196 Yes and yes.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	197
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	198 26. Will zlib work on a 64-bit machine?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	199
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	200 Yes. It has been tested on 64-bit machines, and has no dependence on any
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	201 data types being limited to 32-bits in length. If you have any
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	202 difficulties, please provide a complete problem report to zlib@gzip.org
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	203
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	204 27. Will zlib decompress data from the PKWare Data Compression Library?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	205
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	206 No. The PKWare DCL uses a completely different compressed data format than
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	207 does PKZIP and zlib. However, you can look in zlib's contrib/blast
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	208 directory for a possible solution to your problem.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	209
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	210 28. Can I access data randomly in a compressed stream?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	211
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	212 No, not without some preparation. If when compressing you periodically use
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	213 Z_FULL_FLUSH, carefully write all the pending data at those points, and
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	214 keep an index of those locations, then you can start decompression at those
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	215 points. You have to be careful to not use Z_FULL_FLUSH too often, since it
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	216 can significantly degrade compression. Alternatively, you can scan a
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	217 deflate stream once to generate an index, and then use that index for
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	218 random access. See examples/zran.c .
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	219
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	220 29. Does zlib work on MVS, OS/390, CICS, etc.?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	221
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	222 It has in the past, but we have not heard of any recent evidence. There
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	223 were working ports of zlib 1.1.4 to MVS, but those links no longer work.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	224 If you know of recent, successful applications of zlib on these operating
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	225 systems, please let us know. Thanks.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	226
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	227 30. Is there some simpler, easier to read version of inflate I can look at to
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	228 understand the deflate format?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	229
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	230 First off, you should read RFC 1951. Second, yes. Look in zlib's
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	231 contrib/puff directory.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	232
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	233 31. Does zlib infringe on any patents?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	234
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	235 As far as we know, no. In fact, that was originally the whole point behind
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	236 zlib. Look here for some more information:
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	237
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	238 http://www.gzip.org/#faq11
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	239
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	240 32. Can zlib work with greater than 4 GB of data?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	241
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	242 Yes. inflate() and deflate() will process any amount of data correctly.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	243 Each call of inflate() or deflate() is limited to input and output chunks
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	244 of the maximum value that can be stored in the compiler's "unsigned int"
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	245 type, but there is no limit to the number of chunks. Note however that the
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	246 strm.total_in and strm_total_out counters may be limited to 4 GB. These
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	247 counters are provided as a convenience and are not used internally by
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	248 inflate() or deflate(). The application can easily set up its own counters
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	249 updated after each call of inflate() or deflate() to count beyond 4 GB.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	250 compress() and uncompress() may be limited to 4 GB, since they operate in a
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	251 single call. gzseek() and gztell() may be limited to 4 GB depending on how
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	252 zlib is compiled. See the zlibCompileFlags() function in zlib.h.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	253
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	254 The word "may" appears several times above since there is a 4 GB limit only
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	255 if the compiler's "long" type is 32 bits. If the compiler's "long" type is
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	256 64 bits, then the limit is 16 exabytes.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	257
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	258 33. Does zlib have any security vulnerabilities?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	259
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	260 The only one that we are aware of is potentially in gzprintf(). If zlib is
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	261 compiled to use sprintf() or vsprintf(), then there is no protection
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	262 against a buffer overflow of an 8K string space (or other value as set by
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	263 gzbuffer()), other than the caller of gzprintf() assuring that the output
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	264 will not exceed 8K. On the other hand, if zlib is compiled to use
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	265 snprintf() or vsnprintf(), which should normally be the case, then there is
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	266 no vulnerability. The ./configure script will display warnings if an
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	267 insecure variation of sprintf() will be used by gzprintf(). Also the
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	268 zlibCompileFlags() function will return information on what variant of
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	269 sprintf() is used by gzprintf().
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	270
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	271 If you don't have snprintf() or vsnprintf() and would like one, you can
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	272 find a portable implementation here:
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	273
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	274 http://www.ijs.si/software/snprintf/
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	275
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	276 Note that you should be using the most recent version of zlib. Versions
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	277 1.1.3 and before were subject to a double-free vulnerability, and versions
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	278 1.2.1 and 1.2.2 were subject to an access exception when decompressing
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	279 invalid compressed data.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	280
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	281 34. Is there a Java version of zlib?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	282
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	283 Probably what you want is to use zlib in Java. zlib is already included
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	284 as part of the Java SDK in the java.util.zip package. If you really want
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	285 a version of zlib written in the Java language, look on the zlib home
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	286 page for links: http://zlib.net/ .
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	287
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	288 35. I get this or that compiler or source-code scanner warning when I crank it
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	289 up to maximally-pedantic. Can't you guys write proper code?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	290
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	291 Many years ago, we gave up attempting to avoid warnings on every compiler
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	292 in the universe. It just got to be a waste of time, and some compilers
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	293 were downright silly as well as contradicted each other. So now, we simply
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	294 make sure that the code always works.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	295
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	296 36. Valgrind (or some similar memory access checker) says that deflate is
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	297 performing a conditional jump that depends on an uninitialized value.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	298 Isn't that a bug?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	299
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	300 No. That is intentional for performance reasons, and the output of deflate
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	301 is not affected. This only started showing up recently since zlib 1.2.x
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	302 uses malloc() by default for allocations, whereas earlier versions used
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	303 calloc(), which zeros out the allocated memory. Even though the code was
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	304 correct, versions 1.2.4 and later was changed to not stimulate these
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	305 checkers.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	306
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	307 37. Will zlib read the (insert any ancient or arcane format here) compressed
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	308 data format?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	309
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	310 Probably not. Look in the comp.compression FAQ for pointers to various
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	311 formats and associated software.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	312
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	313 38. How can I encrypt/decrypt zip files with zlib?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	314
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	315 zlib doesn't support encryption. The original PKZIP encryption is very
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	316 weak and can be broken with freely available programs. To get strong
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	317 encryption, use GnuPG, http://www.gnupg.org/ , which already includes zlib
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	318 compression. For PKZIP compatible "encryption", look at
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	319 http://www.info-zip.org/
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	320
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	321 39. What's the difference between the "gzip" and "deflate" HTTP 1.1 encodings?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	322
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	323 "gzip" is the gzip format, and "deflate" is the zlib format. They should
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	324 probably have called the second one "zlib" instead to avoid confusion with
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	325 the raw deflate compressed data format. While the HTTP 1.1 RFC 2616
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	326 correctly points to the zlib specification in RFC 1950 for the "deflate"
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	327 transfer encoding, there have been reports of servers and browsers that
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	328 incorrectly produce or expect raw deflate data per the deflate
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	329 specification in RFC 1951, most notably Microsoft. So even though the
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	330 "deflate" transfer encoding using the zlib format would be the more
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	331 efficient approach (and in fact exactly what the zlib format was designed
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	332 for), using the "gzip" transfer encoding is probably more reliable due to
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	333 an unfortunate choice of name on the part of the HTTP 1.1 authors.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	334
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	335 Bottom line: use the gzip format for HTTP 1.1 encoding.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	336
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	337 40. Does zlib support the new "Deflate64" format introduced by PKWare?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	338
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	339 No. PKWare has apparently decided to keep that format proprietary, since
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	340 they have not documented it as they have previous compression formats. In
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	341 any case, the compression improvements are so modest compared to other more
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	342 modern approaches, that it's not worth the effort to implement.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	343
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	344 41. I'm having a problem with the zip functions in zlib, can you help?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	345
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	346 There are no zip functions in zlib. You are probably using minizip by
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	347 Giles Vollant, which is found in the contrib directory of zlib. It is not
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	348 part of zlib. In fact none of the stuff in contrib is part of zlib. The
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	349 files in there are not supported by the zlib authors. You need to contact
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	350 the authors of the respective contribution for help.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	351
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	352 42. The match.asm code in contrib is under the GNU General Public License.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	353 Since it's part of zlib, doesn't that mean that all of zlib falls under the
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	354 GNU GPL?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	355
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	356 No. The files in contrib are not part of zlib. They were contributed by
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	357 other authors and are provided as a convenience to the user within the zlib
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	358 distribution. Each item in contrib has its own license.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	359
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	360 43. Is zlib subject to export controls? What is its ECCN?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	361
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	362 zlib is not subject to export controls, and so is classified as EAR99.
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	363
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	364 44. Can you please sign these lengthy legal documents and fax them back to us
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	365 so that we can use your software in our product?
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	366
b50eed0cc0ef ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. Franz Glasner <fzglas.hg@dom66.de> parents: diff changeset	367 No. Go away. Shoo.

Mercurial > hgrepos > Python2 > PyMuPDF

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