{ "mode": "info", "parameter": "gzip", "section": "", "url": "https://www.chedong.com/phpMan.php/info/gzip/json", "generated": "2026-06-08T13:12:14Z", "sections": { "GNU Gzip: General file (de)compression": { "content": "This manual is for GNU Gzip (version 1.10), and documents commands for\ncompressing and decompressing data.\n\nCopyright (C) 1998-1999, 2001-2002, 2006-2007, 2009-2018 Free Software\nFoundation, Inc.\n\nCopyright (C) 1992, 1993 Jean-loup Gailly\n\nPermission is granted to copy, distribute and/or modify this\ndocument under the terms of the GNU Free Documentation License,\nVersion 1.3 or any later version published by the Free Software\nFoundation; with no Invariant Sections, with no Front-Cover Texts,\nand with no Back-Cover Texts. A copy of the license is included in\nthe section entitled \"GNU Free Documentation License\".\n\n* Menu:\n\n* Overview::\t\tPreliminary information.\n* Sample::\t\tSample output from 'gzip'.\n* Invoking gzip::\tHow to run 'gzip'.\n* Advanced usage::\tConcatenated files.\n* Environment::\t\tEnvironment variables.\n* Tapes:: Using 'gzip' on tapes.\n* Problems::\t\tReporting bugs.\n* GNU Free Documentation License:: Copying and sharing this manual.\n* Concept index:: Index of concepts.\n\nFile: gzip.info, Node: Overview, Next: Sample, Prev: Top, Up: Top\n", "subsections": [] }, "1 Overview": { "content": "'gzip' reduces the size of the named files using Lempel-Ziv coding\n(LZ77). Whenever possible, each file is replaced by one with the\nextension '.gz', while keeping the same ownership modes, access and\nmodification times. (The default extension is 'z' for MSDOS, OS/2 FAT\nand Atari.) If no files are specified or if a file name is '-', the\nstandard input is compressed to the standard output. 'gzip' will only\nattempt to compress regular files. In particular, it will ignore\nsymbolic links.\n\nIf the new file name is too long for its file system, 'gzip'\ntruncates it. 'gzip' attempts to truncate only the parts of the file\nname longer than 3 characters. (A part is delimited by dots.) If the\nname consists of small parts only, the longest parts are truncated. For\nexample, if file names are limited to 14 characters, gzip.msdos.exe is\ncompressed to gzi.msd.exe.gz. Names are not truncated on systems which\ndo not have a limit on file name length.\n\nBy default, 'gzip' keeps the original file name in the compressed\nfile. This can be useful when decompressing the file with '-N' if the\ncompressed file name was truncated after a file transfer.\n\nIf the original is a regular file, 'gzip' by default keeps its\ntimestamp in the compressed file. This can be useful when decompressing\nthe file with '-N' if the timestamp was not preserved after a file\ntransfer. However, due to limitations in the current 'gzip' file\nformat, fractional seconds are discarded. Also, timestamps must fall\nwithin the range 1970-01-01 00:00:01 through 2106-02-07 06:28:15 UTC,\nand hosts whose operating systems use 32-bit timestamps are further\nrestricted to timestamps no later than 2038-01-19 03:14:07 UTC. The\nupper bounds assume the typical case where leap seconds are ignored.\n\nCompressed files can be restored to their original form using 'gzip\n-d' or 'gunzip' or 'zcat'. If the original name saved in the compressed\nfile is not suitable for its file system, a new name is constructed from\nthe original one to make it legal.\n\n'gunzip' takes a list of files on its command line and replaces each\nfile whose name ends with '.gz', '.z' '-gz', '-z', or 'z' (ignoring\ncase) and which begins with the correct magic number with an\nuncompressed file without the original extension. 'gunzip' also\nrecognizes the special extensions '.tgz' and '.taz' as shorthands for\n'.tar.gz' and '.tar.Z' respectively. When compressing, 'gzip' uses the\n'.tgz' extension if necessary instead of truncating a file with a '.tar'\nextension.\n\n'gunzip' can currently decompress files created by 'gzip', 'zip',\n'compress' or 'pack'. The detection of the input format is automatic.\nWhen using the first two formats, 'gunzip' checks a 32 bit CRC (cyclic\nredundancy check). For 'pack', 'gunzip' checks the uncompressed length.\nThe 'compress' format was not designed to allow consistency checks.\nHowever 'gunzip' is sometimes able to detect a bad '.Z' file. If you\nget an error when uncompressing a '.Z' file, do not assume that the '.Z'\nfile is correct simply because the standard 'uncompress' does not\ncomplain. This generally means that the standard 'uncompress' does not\ncheck its input, and happily generates garbage output. The SCO\n'compress -H' format (LZH compression method) does not include a CRC but\nalso allows some consistency checks.\n\nFiles created by 'zip' can be uncompressed by 'gzip' only if they\nhave a single member compressed with the \"deflation\" method. This\nfeature is only intended to help conversion of 'tar.zip' files to the\n'tar.gz' format. To extract a 'zip' file with a single member, use a\ncommand like 'gunzip .\n\nThis is the output of the command 'gzip -v texinfo.tex':\n\ntexinfo.tex: 69.3% -- replaced with texinfo.tex.gz\n\nThe following command will find all regular '.gz' files in the\ncurrent directory and subdirectories (skipping file names that contain\nnewlines), and extract them in place without destroying the original,\nstopping on the first failure:\n\nfind . -name '*\n*' -prune -o -name '*.gz' -type f -print |\nsed \"\ns/'/'\\\\\\\\''/g\ns/^\\\\(.*\\\\)\\\\.gz$/gunzip <'\\\\1.gz' >'\\\\1'/\n\" |\nsh -e\n\nFile: gzip.info, Node: Invoking gzip, Next: Advanced usage, Prev: Sample, Up: Top\n", "subsections": [] }, "3 Invoking 'gzip'": { "content": "The format for running the 'gzip' program is:\n\ngzip OPTION ...\n\n'gzip' supports the following options:\n\n'--stdout'\n'--to-stdout'\n'-c'\nWrite output on standard output; keep original files unchanged. If\nthere are several input files, the output consists of a sequence of\nindependently compressed members. To obtain better compression,\nconcatenate all input files before compressing them.\n\n'--decompress'\n'--uncompress'\n'-d'\nDecompress.\n\n'--force'\n'-f'\nForce compression or decompression even if the file has multiple\nlinks or the corresponding file already exists, or if the\ncompressed data is read from or written to a terminal. If the\ninput data is not in a format recognized by 'gzip', and if the\noption '--stdout' is also given, copy the input data without change\nto the standard output: let 'zcat' behave as 'cat'. If '-f' is not\ngiven, and when not running in the background, 'gzip' prompts to\nverify whether an existing file should be overwritten.\n\n'--help'\n'-h'\nPrint an informative help message describing the options then quit.\n\n'--keep'\n'-k'\nKeep (don't delete) input files during compression or\ndecompression.\n\n'--list'\n'-l'\nFor each compressed file, list the following fields:\n\ncompressed size: size of the compressed file\nuncompressed size: size of the uncompressed file\nratio: compression ratio (0.0% if unknown)\nuncompressedname: name of the uncompressed file\n\nThe uncompressed size is given as -1 for files not in 'gzip'\nformat, such as compressed '.Z' files. To get the uncompressed\nsize for such a file, you can use:\n\nzcat file.Z | wc -c\n\nIn combination with the '--verbose' option, the following fields\nare also displayed:\n\nmethod: compression method (deflate,compress,lzh,pack)\ncrc: the 32-bit CRC of the uncompressed data\ndate & time: timestamp for the uncompressed file\n\nThe CRC is given as ffffffff for a file not in gzip format.\n\nWith '--verbose', the size totals and compression ratio for all\nfiles is also displayed, unless some sizes are unknown. With\n'--quiet', the title and totals lines are not displayed.\n\nThe 'gzip' format represents the input size modulo 2^32, so the\nuncompressed size and compression ratio are listed incorrectly for\nuncompressed files 4 GiB and larger. To work around this problem,\nyou can use the following command to discover a large uncompressed\nfile's true size:\n\nzcat file.gz | wc -c\n\n'--license'\n'-L'\nDisplay the 'gzip' license then quit.\n\n'--no-name'\n'-n'\nWhen compressing, do not save the original file name and timestamp\nby default. (The original name is always saved if the name had to\nbe truncated.) When decompressing, do not restore the original\nfile name if present (remove only the 'gzip' suffix from the\ncompressed file name) and do not restore the original timestamp if\npresent (copy it from the compressed file). This option is the\ndefault when decompressing.\n\n'--name'\n'-N'\nWhen compressing, always save the original file name, and save the\noriginal timestamp if the original is a regular file; this is the\ndefault. When decompressing, restore the original file name and\ntimestamp if present. This option is useful on systems which have\na limit on file name length or when the timestamp has been lost\nafter a file transfer.\n\n'--quiet'\n'-q'\nSuppress all warning messages.\n\n'--recursive'\n'-r'\nTravel the directory structure recursively. If any of the file\nnames specified on the command line are directories, 'gzip' will\ndescend into the directory and compress all the files it finds\nthere (or decompress them in the case of 'gunzip').\n\n'--rsyncable'\nCater better to the 'rsync' program by periodically resetting the\ninternal structure of the compressed data stream. This lets the\n'rsync' program take advantage of similarities in the uncompressed\ninput when synchronizing two files compressed with this flag. The\ncost: the compressed output is usually about one percent larger.\n\n'--suffix SUF'\n'-S SUF'\nUse suffix SUF instead of '.gz'. Any suffix can be given, but\nsuffixes other than '.z' and '.gz' should be avoided to avoid\nconfusion when files are transferred to other systems. A null\nsuffix forces gunzip to try decompression on all given files\nregardless of suffix, as in:\n\ngunzip -S \"\" * (*.* for MSDOS)\n\nPrevious versions of gzip used the '.z' suffix. This was changed\nto avoid a conflict with 'pack'.\n\n'--synchronous'\nUse synchronous output, by transferring output data to the output\nfile's storage device when the file system supports this. Because\nfile system data can be cached, without this option if the system\ncrashes around the time a command like 'gzip FOO' is run the user\nmight lose both 'FOO' and 'FOO.gz'; this is the default with\n'gzip', just as it is the default with most applications that move\ndata. When this option is used, 'gzip' is safer but can be\nconsiderably slower.\n\n'--test'\n'-t'\nTest. Check the compressed file integrity.\n\n'--verbose'\n'-v'\nVerbose. Display the name and percentage reduction for each file\ncompressed.\n\n'--version'\n'-V'\nVersion. Display the version number and compilation options, then\nquit.\n\n'--fast'\n'--best'\n'-N'\nRegulate the speed of compression using the specified digit N,\nwhere '-1' or '--fast' indicates the fastest compression method\n(less compression) and '--best' or '-9' indicates the slowest\ncompression method (optimal compression). The default compression\nlevel is '-6' (that is, biased towards high compression at expense\nof speed).\n\nFile: gzip.info, Node: Advanced usage, Next: Environment, Prev: Invoking gzip, Up: Top\n", "subsections": [] }, "4 Advanced usage": { "content": "Multiple compressed files can be concatenated. In this case, 'gunzip'\nwill extract all members at once. If one member is damaged, other\nmembers might still be recovered after removal of the damaged member.\nBetter compression can be usually obtained if all members are\ndecompressed and then recompressed in a single step.\n\nThis is an example of concatenating 'gzip' files:\n\ngzip -c file1 > foo.gz\ngzip -c file2 >> foo.gz\n\nThen\n\ngunzip -c foo\n\nis equivalent to\n\ncat file1 file2\n\nIn case of damage to one member of a '.gz' file, other members can\nstill be recovered (if the damaged member is removed). However, you can\nget better compression by compressing all members at once:\n\ncat file1 file2 | gzip > foo.gz\n\ncompresses better than\n\ngzip -c file1 file2 > foo.gz\n\nIf you want to recompress concatenated files to get better\ncompression, do:\n\nzcat old.gz | gzip > new.gz\n\nIf a compressed file consists of several members, the uncompressed\nsize and CRC reported by the '--list' option applies to the last member\nonly. If you need the uncompressed size for all members, you can use:\n\nzcat file.gz | wc -c\n\nIf you wish to create a single archive file with multiple members so\nthat members can later be extracted independently, use an archiver such\nas 'tar' or 'zip'. GNU 'tar' supports the '-z' option to invoke 'gzip'\ntransparently. 'gzip' is designed as a complement to 'tar', not as a\nreplacement.\n\nFile: gzip.info, Node: Environment, Next: Tapes, Prev: Advanced usage, Up: Top\n", "subsections": [] }, "5 Environment": { "content": "The obsolescent environment variable 'GZIP' can hold a set of default\noptions for 'gzip'. These options are interpreted first and can be\noverwritten by explicit command line parameters. As this can cause\nproblems when using scripts, this feature is supported only for options\nthat are reasonably likely to not cause too much harm, and 'gzip' warns\nif it is used. This feature will be removed in a future release of\n'gzip'.\n\nYou can use an alias or script instead. For example, if 'gzip' is in\nthe directory '/usr/bin' you can prepend '$HOME/bin' to your 'PATH' and\ncreate an executable script '$HOME/bin/gzip' containing the following:\n\n#! /bin/sh\nexport PATH=/usr/bin\nexec gzip -9 \"$@\"\n\nThe following environment variables are applicable only when using\n'gzip' on IBM Z mainframes supporting DEFLATE COMPRESSION CALL\ninstruction:\n\n'DFLTCC'\nWhether DEFLATE COMPRESSION CALL should be used. Default value is\n'1'. Set this to '0' to disable DEFLATE COMPRESSION CALL\naltogether.\n\n'DFLTCCLEVELMASK'\nCompression levels on which DEFLATE COMPRESSION CALL should be\nused. Represented as a bit mask in decimal or hexadecimal form,\nwhere each bit corresponds to a compression level. Default value\nis '2', which means level 1 only. In order to make use of DEFLATE\nCOMPRESSION CALL by default, that is, on levels 1-6, set this to\n'0x7e'.\n\n'DFLTCCBLOCKSIZE'\nSize of deflate blocks produced by DEFLATE COMPRESSION CALL in\nbytes in decimal or hexadecimal form. Default value is '1048576'\n(1 megabyte). When using DEFLATE COMPRESSION CALL to compress a\nfile containing heterogeneous data (e.g. a '.tar' archive\ncontaining text and binary files), setting this to a smaller value\nmay improve compression ratio.\n\n'DFLTCCFIRSTFHTBLOCKSIZE'\nSize of the first fixed deflate block produced by DEFLATE\nCOMPRESSION CALL in bytes in decimal or hexadecimal form. Default\nvalue is '4096' (4 kilobytes). When using DEFLATE COMPRESSION CALL\nto compress a small file, setting this to a larger value may\nimprove compression ratio.\n\n'DFLTCCRIBM'\nValue of \"Reserved for IBM\" field of DEFLATE COMPRESSION CALL\nparameter block. Default value is '0'.\n\n'SOURCEDATEEPOCH'\nIf set to any value, disables compression with DEFLATE COMPRESSION\nCALL. This variable is normally set during reproducible builds, and\nin such cases DEFLATE COMPRESSION CALL needs to be disabled,\nbecause its output may be not reproducible.\n\nFile: gzip.info, Node: Tapes, Next: Problems, Prev: Environment, Up: Top\n", "subsections": [] }, "6 Using 'gzip' on tapes": { "content": "When writing compressed data to a tape, it is generally necessary to pad\nthe output with zeroes up to a block boundary. When the data is read\nand the whole block is passed to 'gunzip' for decompression, 'gunzip'\ndetects that there is extra trailing garbage after the compressed data\nand emits a warning by default if the garbage contains nonzero bytes.\nYou can use the '--quiet' option to suppress the warning.\n\nFile: gzip.info, Node: Problems, Next: GNU Free Documentation License, Prev: Tapes, Up: Top\n", "subsections": [] }, "7 Reporting Bugs": { "content": "If you find a bug in 'gzip', please send electronic mail to\n. Include the version number, which you can find by\nrunning 'gzip -V'. Also include in your message the hardware and\noperating system, the compiler used to compile 'gzip', a description of\nthe bug behavior, and the input to 'gzip' that triggered the bug.\n\nFile: gzip.info, Node: GNU Free Documentation License, Next: Concept index, Prev: Problems, Up: Top\n", "subsections": [] }, "Appendix A GNU Free Documentation License": { "content": "Version 1.3, 3 November 2008\n\nCopyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.\n\n\nEveryone is permitted to copy and distribute verbatim copies\nof this license document, but changing it is not allowed.\n\n0. PREAMBLE\n\nThe purpose of this License is to make a manual, textbook, or other\nfunctional and useful document \"free\" in the sense of freedom: to\nassure everyone the effective freedom to copy and redistribute it,\nwith or without modifying it, either commercially or\nnoncommercially. Secondarily, this License preserves for the\nauthor and publisher a way to get credit for their work, while not\nbeing considered responsible for modifications made by others.\n\nThis License is a kind of \"copyleft\", which means that derivative\nworks of the document must themselves be free in the same sense.\nIt complements the GNU General Public License, which is a copyleft\nlicense designed for free software.\n\nWe have designed this License in order to use it for manuals for\nfree software, because free software needs free documentation: a\nfree program should come with manuals providing the same freedoms\nthat the software does. But this License is not limited to\nsoftware manuals; it can be used for any textual work, regardless\nof subject matter or whether it is published as a printed book. We\nrecommend this License principally for works whose purpose is\ninstruction or reference.\n\n1. APPLICABILITY AND DEFINITIONS\n\nThis License applies to any manual or other work, in any medium,\nthat contains a notice placed by the copyright holder saying it can\nbe distributed under the terms of this License. Such a notice\ngrants a world-wide, royalty-free license, unlimited in duration,\nto use that work under the conditions stated herein. The\n\"Document\", below, refers to any such manual or work. Any member\nof the public is a licensee, and is addressed as \"you\". You accept\nthe license if you copy, modify or distribute the work in a way\nrequiring permission under copyright law.\n\nA \"Modified Version\" of the Document means any work containing the\nDocument or a portion of it, either copied verbatim, or with\nmodifications and/or translated into another language.\n\nA \"Secondary Section\" is a named appendix or a front-matter section\nof the Document that deals exclusively with the relationship of the\npublishers or authors of the Document to the Document's overall\nsubject (or to related matters) and contains nothing that could\nfall directly within that overall subject. (Thus, if the Document\nis in part a textbook of mathematics, a Secondary Section may not\nexplain any mathematics.) The relationship could be a matter of\nhistorical connection with the subject or with related matters, or\nof legal, commercial, philosophical, ethical or political position\nregarding them.\n\nThe \"Invariant Sections\" are certain Secondary Sections whose\ntitles are designated, as being those of Invariant Sections, in the\nnotice that says that the Document is released under this License.\nIf a section does not fit the above definition of Secondary then it\nis not allowed to be designated as Invariant. The Document may\ncontain zero Invariant Sections. If the Document does not identify\nany Invariant Sections then there are none.\n\nThe \"Cover Texts\" are certain short passages of text that are\nlisted, as Front-Cover Texts or Back-Cover Texts, in the notice\nthat says that the Document is released under this License. A\nFront-Cover Text may be at most 5 words, and a Back-Cover Text may\nbe at most 25 words.\n\nA \"Transparent\" copy of the Document means a machine-readable copy,\nrepresented in a format whose specification is available to the\ngeneral public, that is suitable for revising the document\nstraightforwardly with generic text editors or (for images composed\nof pixels) generic paint programs or (for drawings) some widely\navailable drawing editor, and that is suitable for input to text\nformatters or for automatic translation to a variety of formats\nsuitable for input to text formatters. A copy made in an otherwise\nTransparent file format whose markup, or absence of markup, has\nbeen arranged to thwart or discourage subsequent modification by\nreaders is not Transparent. An image format is not Transparent if\nused for any substantial amount of text. A copy that is not\n\"Transparent\" is called \"Opaque\".\n\nExamples of suitable formats for Transparent copies include plain\nASCII without markup, Texinfo input format, LaTeX input format,\nSGML or XML using a publicly available DTD, and standard-conforming\nsimple HTML, PostScript or PDF designed for human modification.\nExamples of transparent image formats include PNG, XCF and JPG.\nOpaque formats include proprietary formats that can be read and\nedited only by proprietary word processors, SGML or XML for which\nthe DTD and/or processing tools are not generally available, and\nthe machine-generated HTML, PostScript or PDF produced by some word\nprocessors for output purposes only.\n\nThe \"Title Page\" means, for a printed book, the title page itself,\nplus such following pages as are needed to hold, legibly, the\nmaterial this License requires to appear in the title page. For\nworks in formats which do not have any title page as such, \"Title\nPage\" means the text near the most prominent appearance of the\nwork's title, preceding the beginning of the body of the text.\n\nThe \"publisher\" means any person or entity that distributes copies\nof the Document to the public.\n\nA section \"Entitled XYZ\" means a named subunit of the Document\nwhose title either is precisely XYZ or contains XYZ in parentheses\nfollowing text that translates XYZ in another language. (Here XYZ\nstands for a specific section name mentioned below, such as\n\"Acknowledgements\", \"Dedications\", \"Endorsements\", or \"History\".)\nTo \"Preserve the Title\" of such a section when you modify the\nDocument means that it remains a section \"Entitled XYZ\" according\nto this definition.\n\nThe Document may include Warranty Disclaimers next to the notice\nwhich states that this License applies to the Document. These\nWarranty Disclaimers are considered to be included by reference in\nthis License, but only as regards disclaiming warranties: any other\nimplication that these Warranty Disclaimers may have is void and\nhas no effect on the meaning of this License.\n\n2. VERBATIM COPYING\n\nYou may copy and distribute the Document in any medium, either\ncommercially or noncommercially, provided that this License, the\ncopyright notices, and the license notice saying this License\napplies to the Document are reproduced in all copies, and that you\nadd no other conditions whatsoever to those of this License. You\nmay not use technical measures to obstruct or control the reading\nor further copying of the copies you make or distribute. However,\nyou may accept compensation in exchange for copies. If you\ndistribute a large enough number of copies you must also follow the\nconditions in section 3.\n\nYou may also lend copies, under the same conditions stated above,\nand you may publicly display copies.\n\n3. COPYING IN QUANTITY\n\nIf you publish printed copies (or copies in media that commonly\nhave printed covers) of the Document, numbering more than 100, and\nthe Document's license notice requires Cover Texts, you must\nenclose the copies in covers that carry, clearly and legibly, all\nthese Cover Texts: Front-Cover Texts on the front cover, and\nBack-Cover Texts on the back cover. Both covers must also clearly\nand legibly identify you as the publisher of these copies. The\nfront cover must present the full title with all words of the title\nequally prominent and visible. You may add other material on the\ncovers in addition. Copying with changes limited to the covers, as\nlong as they preserve the title of the Document and satisfy these\nconditions, can be treated as verbatim copying in other respects.\n\nIf the required texts for either cover are too voluminous to fit\nlegibly, you should put the first ones listed (as many as fit\nreasonably) on the actual cover, and continue the rest onto\nadjacent pages.\n\nIf you publish or distribute Opaque copies of the Document\nnumbering more than 100, you must either include a machine-readable\nTransparent copy along with each Opaque copy, or state in or with\neach Opaque copy a computer-network location from which the general\nnetwork-using public has access to download using public-standard\nnetwork protocols a complete Transparent copy of the Document, free\nof added material. If you use the latter option, you must take\nreasonably prudent steps, when you begin distribution of Opaque\ncopies in quantity, to ensure that this Transparent copy will\nremain thus accessible at the stated location until at least one\nyear after the last time you distribute an Opaque copy (directly or\nthrough your agents or retailers) of that edition to the public.\n\nIt is requested, but not required, that you contact the authors of\nthe Document well before redistributing any large number of copies,\nto give them a chance to provide you with an updated version of the\nDocument.\n\n4. MODIFICATIONS\n\nYou may copy and distribute a Modified Version of the Document\nunder the conditions of sections 2 and 3 above, provided that you\nrelease the Modified Version under precisely this License, with the\nModified Version filling the role of the Document, thus licensing\ndistribution and modification of the Modified Version to whoever\npossesses a copy of it. In addition, you must do these things in\nthe Modified Version:\n\nA. Use in the Title Page (and on the covers, if any) a title\ndistinct from that of the Document, and from those of previous\nversions (which should, if there were any, be listed in the\nHistory section of the Document). You may use the same title\nas a previous version if the original publisher of that\nversion gives permission.\n\nB. List on the Title Page, as authors, one or more persons or\nentities responsible for authorship of the modifications in\nthe Modified Version, together with at least five of the\nprincipal authors of the Document (all of its principal\nauthors, if it has fewer than five), unless they release you\nfrom this requirement.\n\nC. State on the Title page the name of the publisher of the\nModified Version, as the publisher.\n\nD. Preserve all the copyright notices of the Document.\n\nE. Add an appropriate copyright notice for your modifications\nadjacent to the other copyright notices.\n\nF. Include, immediately after the copyright notices, a license\nnotice giving the public permission to use the Modified\nVersion under the terms of this License, in the form shown in\nthe Addendum below.\n\nG. Preserve in that license notice the full lists of Invariant\nSections and required Cover Texts given in the Document's\nlicense notice.\n\nH. Include an unaltered copy of this License.\n\nI. Preserve the section Entitled \"History\", Preserve its Title,\nand add to it an item stating at least the title, year, new\nauthors, and publisher of the Modified Version as given on the\nTitle Page. If there is no section Entitled \"History\" in the\nDocument, create one stating the title, year, authors, and\npublisher of the Document as given on its Title Page, then add\nan item describing the Modified Version as stated in the\nprevious sentence.\n\nJ. Preserve the network location, if any, given in the Document\nfor public access to a Transparent copy of the Document, and\nlikewise the network locations given in the Document for\nprevious versions it was based on. These may be placed in the\n\"History\" section. You may omit a network location for a work\nthat was published at least four years before the Document\nitself, or if the original publisher of the version it refers\nto gives permission.\n\nK. For any section Entitled \"Acknowledgements\" or \"Dedications\",\nPreserve the Title of the section, and preserve in the section\nall the substance and tone of each of the contributor\nacknowledgements and/or dedications given therein.\n\nL. Preserve all the Invariant Sections of the Document, unaltered\nin their text and in their titles. Section numbers or the\nequivalent are not considered part of the section titles.\n\nM. Delete any section Entitled \"Endorsements\". Such a section\nmay not be included in the Modified Version.\n\nN. Do not retitle any existing section to be Entitled\n\"Endorsements\" or to conflict in title with any Invariant\nSection.\n\nO. Preserve any Warranty Disclaimers.\n\nIf the Modified Version includes new front-matter sections or\nappendices that qualify as Secondary Sections and contain no\nmaterial copied from the Document, you may at your option designate\nsome or all of these sections as invariant. To do this, add their\ntitles to the list of Invariant Sections in the Modified Version's\nlicense notice. These titles must be distinct from any other\nsection titles.\n\nYou may add a section Entitled \"Endorsements\", provided it contains\nnothing but endorsements of your Modified Version by various\nparties--for example, statements of peer review or that the text has\nbeen approved by an organization as the authoritative definition of\na standard.\n\nYou may add a passage of up to five words as a Front-Cover Text,\nand a passage of up to 25 words as a Back-Cover Text, to the end of\nthe list of Cover Texts in the Modified Version. Only one passage\nof Front-Cover Text and one of Back-Cover Text may be added by (or\nthrough arrangements made by) any one entity. If the Document\nalready includes a cover text for the same cover, previously added\nby you or by arrangement made by the same entity you are acting on\nbehalf of, you may not add another; but you may replace the old\none, on explicit permission from the previous publisher that added\nthe old one.\n\nThe author(s) and publisher(s) of the Document do not by this\nLicense give permission to use their names for publicity for or to\nassert or imply endorsement of any Modified Version.\n\n5. COMBINING DOCUMENTS\n\nYou may combine the Document with other documents released under\nthis License, under the terms defined in section 4 above for\nmodified versions, provided that you include in the combination all\nof the Invariant Sections of all of the original documents,\nunmodified, and list them all as Invariant Sections of your\ncombined work in its license notice, and that you preserve all\ntheir Warranty Disclaimers.\n\nThe combined work need only contain one copy of this License, and\nmultiple identical Invariant Sections may be replaced with a single\ncopy. If there are multiple Invariant Sections with the same name\nbut different contents, make the title of each such section unique\nby adding at the end of it, in parentheses, the name of the\noriginal author or publisher of that section if known, or else a\nunique number. Make the same adjustment to the section titles in\nthe list of Invariant Sections in the license notice of the\ncombined work.\n\nIn the combination, you must combine any sections Entitled\n\"History\" in the various original documents, forming one section\nEntitled \"History\"; likewise combine any sections Entitled\n\"Acknowledgements\", and any sections Entitled \"Dedications\". You\nmust delete all sections Entitled \"Endorsements.\"\n\n6. COLLECTIONS OF DOCUMENTS\n\nYou may make a collection consisting of the Document and other\ndocuments released under this License, and replace the individual\ncopies of this License in the various documents with a single copy\nthat is included in the collection, provided that you follow the\nrules of this License for verbatim copying of each of the documents\nin all other respects.\n\nYou may extract a single document from such a collection, and\ndistribute it individually under this License, provided you insert\na copy of this License into the extracted document, and follow this\nLicense in all other respects regarding verbatim copying of that\ndocument.\n\n7. AGGREGATION WITH INDEPENDENT WORKS\n\nA compilation of the Document or its derivatives with other\nseparate and independent documents or works, in or on a volume of a\nstorage or distribution medium, is called an \"aggregate\" if the\ncopyright resulting from the compilation is not used to limit the\nlegal rights of the compilation's users beyond what the individual\nworks permit. When the Document is included in an aggregate, this\nLicense does not apply to the other works in the aggregate which\nare not themselves derivative works of the Document.\n\nIf the Cover Text requirement of section 3 is applicable to these\ncopies of the Document, then if the Document is less than one half\nof the entire aggregate, the Document's Cover Texts may be placed\non covers that bracket the Document within the aggregate, or the\nelectronic equivalent of covers if the Document is in electronic\nform. Otherwise they must appear on printed covers that bracket\nthe whole aggregate.\n\n8. TRANSLATION\n\nTranslation is considered a kind of modification, so you may\ndistribute translations of the Document under the terms of section\n4. Replacing Invariant Sections with translations requires special\npermission from their copyright holders, but you may include\ntranslations of some or all Invariant Sections in addition to the\noriginal versions of these Invariant Sections. You may include a\ntranslation of this License, and all the license notices in the\nDocument, and any Warranty Disclaimers, provided that you also\ninclude the original English version of this License and the\noriginal versions of those notices and disclaimers. In case of a\ndisagreement between the translation and the original version of\nthis License or a notice or disclaimer, the original version will\nprevail.\n\nIf a section in the Document is Entitled \"Acknowledgements\",\n\"Dedications\", or \"History\", the requirement (section 4) to\nPreserve its Title (section 1) will typically require changing the\nactual title.\n\n9. TERMINATION\n\nYou may not copy, modify, sublicense, or distribute the Document\nexcept as expressly provided under this License. Any attempt\notherwise to copy, modify, sublicense, or distribute it is void,\nand will automatically terminate your rights under this License.\n\nHowever, if you cease all violation of this License, then your\nlicense from a particular copyright holder is reinstated (a)\nprovisionally, unless and until the copyright holder explicitly and\nfinally terminates your license, and (b) permanently, if the\ncopyright holder fails to notify you of the violation by some\nreasonable means prior to 60 days after the cessation.\n\nMoreover, your license from a particular copyright holder is\nreinstated permanently if the copyright holder notifies you of the\nviolation by some reasonable means, this is the first time you have\nreceived notice of violation of this License (for any work) from\nthat copyright holder, and you cure the violation prior to 30 days\nafter your receipt of the notice.\n\nTermination of your rights under this section does not terminate\nthe licenses of parties who have received copies or rights from you\nunder this License. If your rights have been terminated and not\npermanently reinstated, receipt of a copy of some or all of the\nsame material does not give you any rights to use it.\n\n10. FUTURE REVISIONS OF THIS LICENSE\n\nThe Free Software Foundation may publish new, revised versions of\nthe GNU Free Documentation License from time to time. Such new\nversions will be similar in spirit to the present version, but may\ndiffer in detail to address new problems or concerns. See\n.\n\nEach version of the License is given a distinguishing version\nnumber. If the Document specifies that a particular numbered\nversion of this License \"or any later version\" applies to it, you\nhave the option of following the terms and conditions either of\nthat specified version or of any later version that has been\npublished (not as a draft) by the Free Software Foundation. If the\nDocument does not specify a version number of this License, you may\nchoose any version ever published (not as a draft) by the Free\nSoftware Foundation. If the Document specifies that a proxy can\ndecide which future versions of this License can be used, that\nproxy's public statement of acceptance of a version permanently\nauthorizes you to choose that version for the Document.\n\n11. RELICENSING\n\n\"Massive Multiauthor Collaboration Site\" (or \"MMC Site\") means any\nWorld Wide Web server that publishes copyrightable works and also\nprovides prominent facilities for anybody to edit those works. A\npublic wiki that anybody can edit is an example of such a server.\nA \"Massive Multiauthor Collaboration\" (or \"MMC\") contained in the\nsite means any set of copyrightable works thus published on the MMC\nsite.\n\n\"CC-BY-SA\" means the Creative Commons Attribution-Share Alike 3.0\nlicense published by Creative Commons Corporation, a not-for-profit\ncorporation with a principal place of business in San Francisco,\nCalifornia, as well as future copyleft versions of that license\npublished by that same organization.\n\n\"Incorporate\" means to publish or republish a Document, in whole or\nin part, as part of another Document.\n\nAn MMC is \"eligible for relicensing\" if it is licensed under this\nLicense, and if all works that were first published under this\nLicense somewhere other than this MMC, and subsequently\nincorporated in whole or in part into the MMC, (1) had no cover\ntexts or invariant sections, and (2) were thus incorporated prior\nto November 1, 2008.\n\nThe operator of an MMC Site may republish an MMC contained in the\nsite under CC-BY-SA on the same site at any time before August 1,\n2009, provided the MMC is eligible for relicensing.\n", "subsections": [ { "name": "ADDENDUM: How to use this License for your documents", "content": "To use this License in a document you have written, include a copy of\nthe License in the document and put the following copyright and license\nnotices just after the title page:\n\nCopyright (C) YEAR YOUR NAME.\nPermission is granted to copy, distribute and/or modify this document\nunder the terms of the GNU Free Documentation License, Version 1.3\nor any later version published by the Free Software Foundation;\nwith no Invariant Sections, no Front-Cover Texts, and no Back-Cover\nTexts. A copy of the license is included in the section entitled ``GNU\nFree Documentation License''.\n\nIf you have Invariant Sections, Front-Cover Texts and Back-Cover\nTexts, replace the \"with...Texts.\" line with this:\n\nwith the Invariant Sections being LIST THEIR TITLES, with\nthe Front-Cover Texts being LIST, and with the Back-Cover Texts\nbeing LIST.\n\nIf you have Invariant Sections without Cover Texts, or some other\ncombination of the three, merge those two alternatives to suit the\nsituation.\n\nIf your document contains nontrivial examples of program code, we\nrecommend releasing these examples in parallel under your choice of free\nsoftware license, such as the GNU General Public License, to permit\ntheir use in free software.\n\nFile: gzip.info, Node: Concept index, Prev: GNU Free Documentation License, Up: Top\n" } ] }, "Appendix B Concept index": { "content": "* Menu:\n\n* bugs: Problems. (line 6)\n* concatenated files: Advanced usage. (line 6)\n* Environment: Environment. (line 6)\n* invoking: Invoking gzip. (line 6)\n* options: Invoking gzip. (line 6)\n* overview: Overview. (line 6)\n* sample: Sample. (line 6)\n* tapes: Tapes. (line 6)\n\n", "subsections": [] } }, "flags": [], "examples": [], "see_also": [] }