1 GNU gzip NEWS -*- outline -*-
3 * Noteworthy changes in release ?.? (????-??-??) [?]
7 'gzip -l' no longer misreports lengths of multimember inputs.
8 [bug introduced in gzip-1.12]
11 * Noteworthy changes in release 1.13 (2023-08-19) [stable]
13 ** Changes in behavior
15 zless now diagnoses gzip failures, if using less 623 or later.
17 When SIGPIPE is ignored, gzip now exits with status 2 (warning)
18 instead of status 1 (error) when writing to a broken pipe. This is
19 more useful with programs like 'less' that treat gzip exit status 2
24 'gzip -d' no longer fails to report invalid compressed data
25 that uses a dictionary distance outside the input window.
26 [bug present since the beginning]
28 Port to C23, which does not allow K&R-style function definitions
29 with parameters, and which does not define __alignas_is_defined.
32 * Noteworthy changes in release 1.12 (2022-04-07) [stable]
34 ** Changes in behavior
36 'gzip -l' no longer misreports file lengths 4 GiB and larger.
37 Previously, 'gzip -l' output the 32-bit value stored in the gzip
38 header even though that is the uncompressed length modulo 2**32.
39 Now, 'gzip -l' calculates the uncompressed length by decompressing
40 the data and counting the resulting bytes. Although this can take
41 much more time, nowadays the correctness pros seem to outweigh the
44 'zless' is no longer installed on platforms lacking 'less'.
48 zgrep applied to a crafted file name with two or more newlines
49 can no longer overwrite an arbitrary, attacker-selected file.
50 This addresses CVE-2022-1271, ZDI-CAN-16587.
51 [bug introduced in gzip-1.3.10]
53 zgrep now names input file on error instead of mislabeling it as
54 "(standard input)", if grep supports the GNU -H and --label options.
56 'zdiff -C 5' no longer misbehaves by treating '5' as a file name.
57 [bug present since the beginning]
59 Configure-time options like --program-prefix now work.
62 * Noteworthy changes in release 1.11 (2021-09-03) [stable]
64 ** Performance improvements
66 IBM Z platforms now support hardware-accelerated deflation.
69 * Noteworthy changes in release 1.10 (2018-12-29) [stable]
71 ** Changes in behavior
73 Compressed gzip output no longer contains the current time as a
74 timestamp when the input is not a regular file. Instead, the output
75 contains a null (zero) timestamp. This makes gzip's behavior more
76 reproducible when used as part of a pipeline. (As a reminder, even
77 regular files will use null timestamps after the year 2106, due to a
78 limitation in the gzip format.)
82 A use of uninitialized memory on some malformed inputs has been fixed.
83 [bug present since the beginning]
85 A few theoretical race conditions in signal handers have been fixed.
86 These bugs most likely do not happen on practical platforms.
87 [bugs present since the beginning]
90 * Noteworthy changes in release 1.9 (2018-01-07) [stable]
94 gzip -d -S SUFFIX file.SUFFIX would fail for any upper-case byte in SUFFIX.
95 E.g., before, this command would fail:
96 $ :|gzip > kT && gzip -d -S T kT
97 gzip: kT: unknown suffix -- ignored
98 [bug present since the beginning]
100 When decompressing data in 'pack' format, gzip no longer mishandles
101 leading zeros in the end-of-block code. [bug introduced in gzip-1.6]
103 When converting from system-dependent time_t format to the 32-bit
104 unsigned MTIME format used in gzip files, if a timestamp does not
105 fit gzip now substitutes zero instead of the timestamp's low-order
106 32 bits, as per Internet RFC 1952. When converting from MTIME to
107 time_t format, if a timestamp does not fit gzip now warns and
108 substitutes the nearest in-range value instead of crashing or
109 silently substituting an implementation-defined value (typically,
110 the timestamp's low-order bits). This affects timestamps before
111 1970 and after 2106, and timestamps after 2038 on platforms with
112 32-bit signed time_t. [bug present since the beginning]
114 Commands implemented via shell scripts are now more consistent about
115 failure status. For example, 'gunzip --help >/dev/full' now
116 consistently exits with status 1 (error), instead of with status 2
117 (warning) on some platforms. [bug present since the beginning]
119 Support for VMS and Amiga has been removed. It was not working anyway,
120 and it reportedly caused file name glitches on MS-Windowsish platforms.
123 * Noteworthy changes in release 1.8 (2016-04-26) [stable]
127 gzip -l no longer falsely reports a write error when writing to a pipe.
128 [bug introduced in gzip-1.7]
130 Port to Oracle Solaris Studio 12 on x86-64.
131 [bug present since at least gzip-1.2.4]
133 When configuring gzip, ./configure DEFS='...-DNO_ASM...' now
134 suppresses assembler again. [bug introduced in gzip-1.3.5]
137 * Noteworthy changes in release 1.7 (2016-03-27) [stable]
139 ** Changes in behavior
141 The GZIP environment variable is now obsolescent; gzip now warns if
142 it is used, and rejects attempts to use dangerous options or operands.
143 You can use an alias or script instead.
145 Installed programs like 'zgrep' now use the PATH environment variable
146 as usual to find subsidiary programs like 'gzip' and 'grep'.
147 Previously they prepended the installation directory to the PATH,
148 which sometimes caused 'make check' to test the wrong gzip executable.
149 [bug introduced in gzip-1.3.13]
153 gzip now accepts the --synchronous option, which causes it to use
154 fsync and similar primitives to transfer output data to the output
155 file's storage device when the file system supports this. Although
156 this option makes gzip safer in the presence of system crashes, it
157 can make gzip considerably slower.
159 gzip now accepts the --rsyncable option. This option is accepted in
160 all modes, but has effect only when compressing: it makes the resulting
161 output more amenable to efficient use of rsync. For example, when a
162 large input file gets a small change, a gzip --rsyncable image of
163 that file will remain largely unchanged, too. Without --rsyncable,
164 even a tiny change in the input could result in a totally different
165 gzip-compressed output file.
169 gzip -k -v no longer reports that files are replaced.
170 [bug present since the beginning]
172 zgrep -f A B C no longer reads A more than once if A is not a regular file.
173 This better supports invocations like 'zgrep -f <(COMMAND) B C' in Bash.
174 [bug introduced in gzip-1.2]
177 * Noteworthy changes in release 1.6 (2013-06-09) [stable]
181 gzip now accepts the --keep (-k) option, for consistency with tools
182 like xz, lzip and bzip2. With this option, gzip no longer removes
183 named input files when compressing or decompressing.
187 gzip -d no longer malfunctions with certain invalid data in 'pack' format.
188 [bug introduced in gzip-0.8]
190 When overwriting, gzip no longer acts as if you typed "y" when you type "n",
191 on some platforms when compiled with optimization.
192 [bug introduced in gzip-1.3.6]
194 zgrep no longer malfunctions with a multi-digit context option like -15.
195 Now, it passes that option to grep (equivalent to -C15) just as it does
196 for single-digit options. [bug introduced in gzip-1.3.12]
198 zmore now acts more like 'more', and is more portable to POSIXish hosts.
201 * Noteworthy changes in release 1.5 (2012-06-17) [stable]
205 gzip -d now decodes and checks header CRC16 checksums as specified by
206 the FHCRC section of Internet RFC 1952.
208 "gzip -d -S '' precious.gz" is now rejected immediately. Before,
209 that command would emulate "rm -i precious.gz", but with an easily-
210 misunderstood prompt. I.e., gzip would ask if it's ok to remove the
211 existing file, "precious.gz". If you made the mistake of saying "yes",
212 it would remove that input file before attempting to uncompress it.
214 gzip -cdf now properly handles input consisting of gzip'd data followed
215 by uncompressed data. Before it would output raw compressed input, too.
216 For example, now "(printf x|gzip; echo y)|gzip -dcf" prints "xy\n",
217 while before it would print "x<compressed data>y\n".
219 gzip -rf no longer compresses files more than once (e.g., replacing
220 FOO with FOO.gz.gz) on file systems such as ZFS where a readdir
221 loop that unlinks and creates files can revisit output files.
224 * Noteworthy changes in release 1.4 (2010-01-20) [stable]
228 gzip -d could segfault and/or clobber the stack, possibly leading to
229 arbitrary code execution. This affects x86_64 but not 32-bit systems.
230 This fixes CVE-2010-0001.
231 For more details, see https://bugzilla.redhat.com/554418
233 gzip -d would fail with a CRC error for some valid inputs.
234 So far, the only valid input known to exhibit this failure was
235 compressed "from FAT filesystem (MS-DOS, OS/2, NT)". In addition,
236 to trigger the failure, your memcpy implementation must copy in
240 * Noteworthy changes in release 1.3.14 (2009-10-30) [beta]
244 gzip no longer fails when there is exactly one trailing NUL byte
245 gzip has always accepted trailing NUL bytes. Note the plural.
247 zdiff would exit with status 2 (indicating an error) rather than 1 to
248 indicate differences when both inputs were compressed and different.
250 zdiff would fail to print differences in two compressed inputs
252 zgrep -f - didn't work
255 * Noteworthy changes in release 1.3.13 (2009-09-30) [stable]
257 ** 'gzip -f foo.gz' now creates a file foo.gz.gz instead of complaining.
261 gzip -d no longer fails with "-" as 2nd or subsequent argument
263 gzip no longer ignores a close-induced write failure, e.g., on NFS
265 gzip -d no longer segfaults on certain invalid inputs
268 Major changes in Gzip 1.3.12 (2007-04-13)
270 * znew now uses $TMPDIR (default /tmp) instead of always using /tmp.
272 * It is now documented that gzip ignores case when examining file name
273 extensions; for example, 'gzip test.Gz' (without -f) fails because
274 the file name ends in '.Gz'.
276 Major changes in Gzip 1.3.11 (2007-02-05)
278 * As per the GNU coding standards, the behavior of gzip and its
279 companion executables no longer depend on the name used to invoke them.
280 For example, 'gzip' and 'gunzip' are no longer hard links;
281 instead, 'gunzip' is now a small program that invokes 'gzip -d'.
283 * zdiff now checks for subsidiary gzip failures, and works around
284 bugs in IRIX 6 sh, Tru64 4.0F ksh, and Solaris 8 bash.
286 Major changes in Gzip 1.3.10 (2006-12-30)
288 * gzip -c and zcat now work on special files, files with special mode bits,
289 and files with multiple hard links.
290 * gzip -q now exits with status 2 (not 1) when SIGPIPE is received.
291 * zcmp and zdiff did not work in the usual case, due to a typo.
292 * zgrep has many bugs fixed with argument handling, special characters,
294 * zless no longer mishandles $%=~ in file names.
296 Gzip 1.3.9 (2006-12-15)
298 * No major changes; only porting fixes.
300 Major changes in Gzip 1.3.8 (2006-12-08)
302 * Fix some gzip problems:
303 - A security fix from Debian 1.3.5-5 was inadvertently omitted.
304 - The assembler is now invoked with --noexecstack if supported,
305 so that gzip can better resist stack-smashing attacks.
307 Major changes in Gzip 1.3.7 (2006-12-06)
309 * Fix some gzip problems:
310 - Refuse to compress setuid or setgid files, or files with the sticky bit.
311 - Fix more race conditions in setting file permissions and owner,
312 removing output files, following symbolic links, and dealing with
314 - Remove most of the code working around ENAMETOOLONG deficiencies.
315 Systems with those deficiencies are long-dead, and the workarounds
316 had race conditions on modern hosts.
317 - Catch CPU time and file size limit signals, too.
318 - Check for read errors when closing files.
319 - Fix a core dump caused by a stray abort mistakenly introduced in 1.3.6.
320 * Fix some gzexe problems:
321 - Improve resistance to denial-of-service attacks.
322 - Fix some quoting and escaping bugs.
323 - Do not assume /tmp is sticky (though it should be!).
324 - Do not assume the working directory can be written.
325 - Rely on PATH in the generated executable, as the man page says.
326 - Don't assume IFS is sane.
327 - Exit with signal's status, if signaled.
329 Major changes in Gzip 1.3.6 (2006-11-20)
331 * Fix some race conditions in setting file timestamps, permissions, and owner.
332 * Fix some race conditions in signal handling.
333 * When gzip exits due to a signal, it exits with the signal's status, not 1.
334 * gzip now restores file timestamps to the resolution supported by the
335 time-setting primitives of the operating system, typically 1 microsecond.
336 Formerly it restored them only to the nearest second.
337 * gzip -r no longer attempts to reset the last-access times of directories
338 it reads, as this messes up when other processes are reading the directories.
339 * The options --version and --help now work on all gzip-installed executables,
340 and now use a format similar to other GNU programs.
341 * The manual is now distributed under the terms of the GNU Free
342 Documentation License without invariant sections or cover texts.
343 * Port to current versions of Autoconf, Automake, and Gnulib.
345 Major changes from 1.3.4 to 1.3.5
346 * gzip now removes any output symlink before writing output file.
347 * zgrep etc. scripts now port to POSIX 1003.1-2001 hosts.
348 * zforce no longer assumes 14-byte file name length limit.
349 * zless is now implemented using less and LESSOPEN, not zmore and PAGER.
350 * assembly-language speedups reenabled; were mistakenly disabled in 1.3.
352 Major changes from 1.3.3 to 1.3.4
353 * Less output is lost when decompressing a truncated file.
354 * The manual is now distributed under the terms of the GNU Free
355 Documentation License.
357 No major changes in 1.3.2 or 1.3.3 (bug fixes only)
359 Major changes from 1.3 to 1.3.1
360 * zgrep now supports --, -H, -h, -L, -l, -C, -d, -m and their long equivalents.
362 Major changes from 1.2.4 to 1.3
363 * Add support for large files, e.g. files larger than 2 GB on Solaris 2.6.
364 * Adjust file size listing format for files larger than 10 GB.
365 * New command `zless'.
366 * `zdiff' now reports exit status like `diff' does.
367 * `zcat' is now always called `zcat', not `gzcat'.
368 Similarly for `zdiff', `zgrep', `zmore', `znew', `zforce'.
369 * Warn about a compressed file's trailing zeros only if verbose,
370 for compatibility with recent versions of GNU tar.
371 * Conform to changes to GNU makefile standards.
372 * Port to Autoconf 2.13.
373 * Convert to Automake.
374 * Fix bugs in the following areas:
375 - files larger than 4 GB
376 - security hole involving symlinks from /tmp
377 - security hole involving long file names
378 - permissions bug when compressing a symbolic link to a file
380 - concatenated compressed files on INBUFSIZ boundaries
381 - porting bugs on hosts with signed chars
382 - porting bug with upper and lower case
383 - porting bug for hosts that reserve the names `basename' or `warning'
385 Major changes from 1.2.3 to 1.2.4
386 * By default, do not restore file name and timestamp from those saved
387 inside the .gz file (behave as 'compress'). Added the --name option
388 to force name and timestamp restoration.
389 * Accept - as synonym for stdin.
390 * Use manlinks=so or ln to support either hard links or .so in man pages
391 * Accept foo.gz~ in zdiff.
392 * Added support for Windows NT
393 * Handle ENAMETOOLONG for strict Posix systems
394 * Use --recursive instead of --recurse to comply with Webster and
396 * Allow installation of shell scripts with a g prefix: make G=g install
397 * Install by default zcat as gzcat if gzcat already exists in path.
398 * Let zmore behave as more when invoked without parameters (give help)
399 * Let gzip --list reject files not in gzip format even with --force.
400 * Don't complain about non gzip files for options -rt or -rl.
401 * Added advice in INSTALL for several systems.
403 Major changes from 1.2.2 to 1.2.3
404 * Don't display the output name when decompressing except with --verbose.
405 * Remove usage of alloca in getopt.c and all makefiles.
406 * Added the zfile shell script in subdirectory sample.
407 * Moved the list of compiler bugs from README to INSTALL.
408 * Added vms/Readme.vms.
410 Major changes from 1.2.1 to 1.2.2
411 * Fix a compilation error on Sun with cc (worked with gcc).
413 Major changes from 1.2 to 1.2.1
414 * Let zmore act as more if the data is not gzipped.
415 * made gzexe more secure (don't rely on PATH).
416 * By default, display output name only when the name was actually truncated.
418 Major changes from 1.1.2 to 1.2
419 * Added the --list option to display the file characteristics.
420 * Added the --no-name option: do not save or restore original filename
421 Save the original name by default.
422 * Allow gunzip --suffix "" to attempt decompression on any file
423 regardless of its extension if an original name is present.
424 * Add support for the SCO compress -H format.
425 * gzip --fast now compresses faster (speed close to that of compress)
426 with degraded compression ratio (but still better than compress).
427 Default level changed to -6 (acts exactly as previous level -5) to
428 be a better indication of its placement in the speed/ratio range.
429 * Use smart name truncation: 123456789012.c -> 123456789.c.gz
430 instead of 12345678901.gz
431 * With --force, let zcat pass non gzip'ed data unchanged (zcat == cat)
432 * Added the zgrep shell script.
433 * Made sub.c useful for 16 bit sound, 24 bit images, etc..
434 * Suppress warnings about suffix for gunzip -r, except with --verbose.
435 * On MSDOS, use .gz extension when possible (files without extension)
436 * Moved the sample programs to a subdirectory sample.
437 * Added a "Special targets" section in INSTALL.
439 Major changes from 1.1.1 to 1.1.2.
440 * Fix serious bug for VMS (-gz not removed when decompressing).
441 * Allow suffix other than .gz in znew.
442 * Do not display compression ratio when decompressing stdin.
443 * In zmore.in, work around brain damaged stty -g (Ultrix).
444 * Display a correct compression ratio for .Z files.
445 * Added .z to .gz renaming script in INTALL.
446 * Allow setting CFLAGS in configure.
448 Major changes from 1.1 to 1.1.1.
449 * Fix serious bug in vms.c (affects Vax/VMS only).
450 * Added --ascii option.
451 * Add workaround in configure.in for Ultrix (quote eval argument)
453 Major changes from 1.0.7 to 1.1.
454 * Use .gz suffix by default, add --suffix option.
455 * Let gunzip accept a "_z" suffix (used by one 'compress' on Vax/VMS).
456 * Quit when reading garbage from stdin instead of reporting an error.
457 * Added makefile for VAX/MMS and support for wildcards on VMS.
458 * Added support for MSC under OS/2.
459 * Added support for Prime/PRIMOS.
460 * Display compression ratio also when decompressing (with --verbose).
461 * Quit after --version (GNU standard)
462 * Use --force to bypass isatty() check
463 * Continue processing other files in case of recoverable error.
464 * Added comparison of zip and gzip in the readme file.
465 * Added small sample programs (ztouch, sub, add)
466 * Use less memory when compiled with -DSMALL_MEM (for MSDOS).
467 * Remove the "off by more than one minute" timestamp kludge
469 Major changes from 1.0.6 to 1.0.7.
470 * Allow zmore to read from standard input (like more).
471 * Support the 68000 (Atari ST) in match.S.
472 * Retry partial writes (required on Linux when gzip is suspended in a pipe).
473 * Allow full pathnames and renamings in gzexe.
474 * Don't let gzexe compress setuid executables or gzip itself.
475 * Added vms/Makefile.gcc for gcc on the Vax.
476 * Allow installation of binaries and shell scripts in different dirs.
477 * Allows complex PAGER variable in zmore (e.g.: PAGER="col -x | more")
478 * Allow installation of zcat as gzcat.
479 * Several small changes for portability to old or weird systems.
480 * Suppress help message and send compressed data to the terminal when
481 gzip is invoked without parameters and without redirection.
482 * Add compile option GNU_STANDARD to respect the GNU coding standards:
483 with -DGNU_STANDARD, behave as gzip even if invoked under the name gunzip.
484 (I don't like the last two changes, which were requested by the FSF.)
486 Major changes from 1.0.5 to 1.0.6.
487 * Let gzexe detect executables that are already gzexe'd.
488 * Keep file attributes in znew and gzexe if cpmod is available.
489 * Don't try restoring record format on VMS (1.0.5 did not work correctly)
490 * Added asm version for 68000 in amiga/match.a.
491 Use asm version for Atari TT and NeXT.
492 * For OS/2, assume HPFS by default, add flag OS2FAT if necessary.
493 * Fixed some bugs in zdiff and define zcmp as a link to zdiff.
496 Major changes from 1.0.4 to 1.0.5.
497 * For VMS, restore the file type for variable record format, otherwise
498 extract in fixed length format (not perfect, but better than
499 forcing all files to be in stream_LF format).
500 * For VMS, use "-z" default suffix and accept a version number in file names.
501 * For Unix, allow compression of files with name ending in 'z'. Use only
502 .z, .*-z, .tgz, .taz as valid gzip extensions. In the last two cases,
503 extract to .tar by default.
504 * On some versions of MSDOS, files with a 3 character extension could not
506 * Garbage collect files in /tmp created by gzexe.
507 * Fix the 'OS code' byte in the gzip header.
508 * For the Amiga, add the missing utime.h and add support for gcc.
511 Major changes from 1.0.3 to 1.0.4.
512 * Added optimized asm version for 68020.
513 * Add support for DJGPP.
515 * Add support for the Atari ST.
516 * Added zforce to rename gzip'ed files with truncated names.
517 * Do not install with name uncompress (some systems rely on the
518 absence of any check in the old uncompress).
519 * Added missing function (fcfree) in msdos/tailor.c
520 * Let gunzip handle .tgz files, and let gzip skip them.
521 * Added -d option (decompress) for gzexe and try preserving file permissions.
522 * Suppress all warnings with -q.
523 * Use GZIP_OPT for VMS to avoid conflict with program name.
524 * ... and many other small changes (see ChangeLog)
527 Major changes from 1.0.2 to 1.0.3
528 * Added -K option for znew to keep old .Z files if smaller
529 * Added -q option (quiet) to cancel -v in GZIP env variable.
530 * Made gzexe safer on systems with filename limitation to 14 chars.
531 * Fixed bugs in handling of GZIP env variable and incorrect free with Turbo C.
534 Major changes from 1.0.1 to 1.0.2
535 * Added env variable GZIP for default options. Example:
536 for sh: GZIP="-8 -v"; export GZIP
537 for csh: setenv GZIP "-8 -v"
538 * Added support for the Amiga.
539 * znew now keeps the old .Z if it is smaller than the .z file.
540 This can happen for some large and very redundant files.
541 * Do not complain about trailing garbage for record oriented IO (Vax/VMS).
542 This implies however that multi-part gzip files are not supported
544 * Added gzexe to compress rarely used executables.
545 * Reduce memory usage (required for MSDOS and useful on all systems).
546 * Preserve timestamp in znew -P (pipe option) if touch -r works.
549 Major changes from 1.0 to 1.0.1
550 * fix trivial errors in the Borland makefile (msdos/Makefile.bor)
553 Major changes from 0.8.2 to 1.0
554 * gzip now runs on Vax/VMS
555 * gzip will not not overwrite files without -f when using /bin/sh in
557 * Support the test option -t for compressed (.Z) files.
558 Allow some data recovery for bad .Z files.
559 * Added makefiles for MSDOS (Only tested for MSC, not Borland).
560 * still more changes to configure for several systems
563 Major changes from 0.8.1 to 0.8.2:
564 * yet more changes to configure for Linux and other systems
565 * Allow zcat on a file with multiple links.
568 Major changes from 0.8 to 0.8.1:
569 * znew has now a pipe option -P to reduce the disk space requirements,
570 but this option does not preserve timestamps.
571 * Fixed some #if directives for compilation with TurboC.
574 Major changes from 0.7 to 0.8:
575 * gzip can now extract .z files created by 'pack'.
576 * configure should no longer believe that every machine is a 386
577 * Fix the entry for /etc/magic in INSTALL.
578 * Add patch for GNU tar 1.11.1 and a pointer to crypt++.el
579 * Uncompress files with multiple links only with -f.
580 * Fix for uncompress of .Z files on 16-bit machines
581 * Create a correct output name for file names of exactly N-1 chars when
582 the system has a limit of N chars.
585 Major changes from 0.6 to 0.7:
586 * Use "make check" instead of "make test".
587 * Keep timestamp and pass options to gzip in znew.
588 * Do not create .z.z files with gzip -r.
589 * Allow again gunzip .zip files (was working in 0.5)
590 * Allow again compilation with TurboC 2.0 (was working in 0.4)
593 Major changes form 0.5 to 0.6:
594 * gunzip reported an error when extracting certain .z files. The .z files
595 produced by gzip 0.5 are correct and can be read by gunzip 0.6.
596 * gunzip now supports multiple compressed members within a single .z file.
597 * Fix the check for i386 in configure.
598 * Added "make test" to check for compiler bugs. (gcc -finline-functions
599 is broken at least on the NeXT.)
600 * Use environment variable PAGER in zmore if it is defined.
601 * Accept gzcat in addition to zcat for people having /usr/bin before
602 /usr/local/bin in their path.
605 ========================================================================
607 Copyright (C) 1999, 2001-2002, 2006-2007, 2009-2024 Free Software Foundation,
609 Copyright (C) 1992, 1993 Jean-loup Gailly
611 Permission is granted to copy, distribute and/or modify this document
612 under the terms of the GNU Free Documentation License, Version 1.3 or
613 any later version published by the Free Software Foundation; with no
614 Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
615 Texts. A copy of the license is included in the ``GNU Free
616 Documentation License'' file as part of this distribution.