gzip - phpMan

File: gzip.info, Node: Top, Next: Overview, Up: (dir)

GNU Gzip: General file (de)compression
**************************************

This manual is for GNU Gzip (version 1.10), and documents commands for
compressing and decompressing data.

Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License,
Version 1.3 or any later version published by the Free Software
Foundation; with no Invariant Sections, with no Front-Cover Texts,
and with no Back-Cover Texts. A copy of the license is included in
the section entitled "GNU Free Documentation License".

* Menu:

* Overview:: Preliminary information.
* Sample:: Sample output from 'gzip'.
* Invoking gzip:: How to run 'gzip'.
* Advanced usage:: Concatenated files.
* Environment:: Environment variables.
* Tapes:: Using 'gzip' on tapes.
* Problems:: Reporting bugs.
* GNU Free Documentation License:: Copying and sharing this manual.
* Concept index:: Index of concepts.

File: gzip.info, Node: Overview, Next: Sample, Prev: Top, Up: Top

1 Overview
**********

'gzip' reduces the size of the named files using Lempel-Ziv coding
(LZ77). Whenever possible, each file is replaced by one with the
extension '.gz', while keeping the same ownership modes, access and
modification times. (The default extension is 'z' for MSDOS, OS/2 FAT
and Atari.) If no files are specified or if a file name is '-', the
standard input is compressed to the standard output. 'gzip' will only
attempt to compress regular files. In particular, it will ignore
symbolic links.

If the new file name is too long for its file system, 'gzip'
truncates it. 'gzip' attempts to truncate only the parts of the file
name longer than 3 characters. (A part is delimited by dots.) If the
name consists of small parts only, the longest parts are truncated. For
example, if file names are limited to 14 characters, gzip.msdos.exe is
compressed to gzi.msd.exe.gz. Names are not truncated on systems which
do not have a limit on file name length.

By default, 'gzip' keeps the original file name in the compressed
file. This can be useful when decompressing the file with '-N' if the
compressed file name was truncated after a file transfer.

If the original is a regular file, 'gzip' by default keeps its
timestamp in the compressed file. This can be useful when decompressing
the file with '-N' if the timestamp was not preserved after a file
transfer. However, due to limitations in the current 'gzip' file
format, fractional seconds are discarded. Also, timestamps must fall
within the range 1970-01-01 00:00:01 through 2106-02-07 06:28:15 UTC,
and hosts whose operating systems use 32-bit timestamps are further
restricted to timestamps no later than 2038-01-19 03:14:07 UTC. The
upper bounds assume the typical case where leap seconds are ignored.

Compressed files can be restored to their original form using 'gzip
-d' or 'gunzip' or 'zcat'. If the original name saved in the compressed
file is not suitable for its file system, a new name is constructed from
the original one to make it legal.

'gunzip' takes a list of files on its command line and replaces each
file whose name ends with '.gz', '.z' '-gz', '-z', or '_z' (ignoring
case) and which begins with the correct magic number with an
uncompressed file without the original extension. 'gunzip' also
recognizes the special extensions '.tgz' and '.taz' as shorthands for
'.tar.gz' and '.tar.Z' respectively. When compressing, 'gzip' uses the
'.tgz' extension if necessary instead of truncating a file with a '.tar'
extension.

'gunzip' can currently decompress files created by 'gzip', 'zip',
'compress' or 'pack'. The detection of the input format is automatic.
When using the first two formats, 'gunzip' checks a 32 bit CRC (cyclic
redundancy check). For 'pack', 'gunzip' checks the uncompressed length.
The 'compress' format was not designed to allow consistency checks.
However 'gunzip' is sometimes able to detect a bad '.Z' file. If you
get an error when uncompressing a '.Z' file, do not assume that the '.Z'
file is correct simply because the standard 'uncompress' does not
complain. This generally means that the standard 'uncompress' does not
check its input, and happily generates garbage output. The SCO
'compress -H' format (LZH compression method) does not include a CRC but
also allows some consistency checks.

Files created by 'zip' can be uncompressed by 'gzip' only if they
have a single member compressed with the "deflation" method. This
feature is only intended to help conversion of 'tar.zip' files to the
'tar.gz' format. To extract a 'zip' file with a single member, use a
command like 'gunzip <foo.zip' or 'gunzip -S .zip foo.zip'. To extract
'zip' files with several members, use 'unzip' instead of 'gunzip'.

'zcat' is identical to 'gunzip -c'. 'zcat' uncompresses either a
list of files on the command line or its standard input and writes the
uncompressed data on standard output. 'zcat' will uncompress files that
have the correct magic number whether they have a '.gz' suffix or not.

'gzip' uses the Lempel-Ziv algorithm used in 'zip' and PKZIP. The
amount of compression obtained depends on the size of the input and the
distribution of common substrings. Typically, text such as source code
or English is reduced by 60-70%. Compression is generally much better
than that achieved by LZW (as used in 'compress'), Huffman coding (as
used in 'pack'), or adaptive Huffman coding ('compact').

Compression is always performed, even if the compressed file is
slightly larger than the original. The worst case expansion is a few
bytes for the 'gzip' file header, plus 5 bytes every 32K block, or an
expansion ratio of 0.015% for large files. Note that the actual number
of used disk blocks almost never increases. 'gzip' normally preserves
the mode, ownership and timestamps of files when compressing or
decompressing.

The 'gzip' file format is specified in P. Deutsch, GZIP file format
specification version 4.3, Internet RFC 1952
(https://www.ietf.org/rfc/rfc1952.txt) (May 1996). The 'zip' deflation
format is specified in P. Deutsch, DEFLATE Compressed Data Format
Specification version 1.3, Internet RFC 1951
(https://www.ietf.org/rfc/rfc1951.txt) (May 1996).

File: gzip.info, Node: Sample, Next: Invoking gzip, Prev: Overview, Up: Top

2 Sample output
***************

Here are some realistic examples of running 'gzip'.

This is the output of the command 'gzip -h':

Usage: gzip [OPTION]... [FILE]...
Compress or uncompress FILEs (by default, compress FILES in-place).

Mandatory arguments to long options are mandatory for short options too.

-c, --stdout write on standard output, keep original files unchanged
-d, --decompress decompress
-f, --force force overwrite of output file and compress links
-h, --help give this help
-k, --keep keep (don't delete) input files
-l, --list list compressed file contents
-L, --license display software license
-n, --no-name do not save or restore the original name and timestamp
-N, --name save or restore the original name and timestamp
-q, --quiet suppress all warnings
-r, --recursive operate recursively on directories
--rsyncable make rsync-friendly archive
-S, --suffix=SUF use suffix SUF on compressed files
--synchronous synchronous output (safer if system crashes, but slower)
-t, --test test compressed file integrity
-v, --verbose verbose mode
-V, --version display version number
-1, --fast compress faster
-9, --best compress better

With no FILE, or when FILE is -, read standard input.

Report bugs to <bug-gzip AT gnu.org>.

This is the output of the command 'gzip -v texinfo.tex':

texinfo.tex: 69.3% -- replaced with texinfo.tex.gz

The following command will find all regular '.gz' files in the
current directory and subdirectories (skipping file names that contain
newlines), and extract them in place without destroying the original,
stopping on the first failure:

find . -name '*
*' -prune -o -name '*.gz' -type f -print |
sed "
s/'/'\\\\''/g
s/^\$.*\$\\.gz$/gunzip <'\\1.gz' >'\\1'/
" |
sh -e

File: gzip.info, Node: Invoking gzip, Next: Advanced usage, Prev: Sample, Up: Top

3 Invoking 'gzip'
*****************

The format for running the 'gzip' program is:

gzip OPTION ...

'gzip' supports the following options:

'--stdout'
'--to-stdout'
'-c'
Write output on standard output; keep original files unchanged. If
there are several input files, the output consists of a sequence of
independently compressed members. To obtain better compression,
concatenate all input files before compressing them.

'--decompress'
'--uncompress'
'-d'
Decompress.

'--force'
'-f'
Force compression or decompression even if the file has multiple
links or the corresponding file already exists, or if the
compressed data is read from or written to a terminal. If the
input data is not in a format recognized by 'gzip', and if the
option '--stdout' is also given, copy the input data without change
to the standard output: let 'zcat' behave as 'cat'. If '-f' is not
given, and when not running in the background, 'gzip' prompts to
verify whether an existing file should be overwritten.

'--help'
'-h'
Print an informative help message describing the options then quit.

'--keep'
'-k'
Keep (don't delete) input files during compression or
decompression.

'--list'
'-l'
For each compressed file, list the following fields:

compressed size: size of the compressed file
uncompressed size: size of the uncompressed file
ratio: compression ratio (0.0% if unknown)
uncompressed_name: name of the uncompressed file

The uncompressed size is given as -1 for files not in 'gzip'
format, such as compressed '.Z' files. To get the uncompressed
size for such a file, you can use:

zcat file.Z | wc -c

In combination with the '--verbose' option, the following fields
are also displayed:

method: compression method (deflate,compress,lzh,pack)
crc: the 32-bit CRC of the uncompressed data
date & time: timestamp for the uncompressed file

The CRC is given as ffffffff for a file not in gzip format.

With '--verbose', the size totals and compression ratio for all
files is also displayed, unless some sizes are unknown. With
'--quiet', the title and totals lines are not displayed.

The 'gzip' format represents the input size modulo 2^32, so the
uncompressed size and compression ratio are listed incorrectly for
uncompressed files 4 GiB and larger. To work around this problem,
you can use the following command to discover a large uncompressed
file's true size:

zcat file.gz | wc -c

'--license'
'-L'
Display the 'gzip' license then quit.

'--no-name'
'-n'
When compressing, do not save the original file name and timestamp
by default. (The original name is always saved if the name had to
be truncated.) When decompressing, do not restore the original
file name if present (remove only the 'gzip' suffix from the
compressed file name) and do not restore the original timestamp if
present (copy it from the compressed file). This option is the
default when decompressing.

'--name'
'-N'
When compressing, always save the original file name, and save the
original timestamp if the original is a regular file; this is the
default. When decompressing, restore the original file name and
timestamp if present. This option is useful on systems which have
a limit on file name length or when the timestamp has been lost
after a file transfer.

'--quiet'
'-q'
Suppress all warning messages.

'--recursive'
'-r'
Travel the directory structure recursively. If any of the file
names specified on the command line are directories, 'gzip' will
descend into the directory and compress all the files it finds
there (or decompress them in the case of 'gunzip').

'--rsyncable'
Cater better to the 'rsync' program by periodically resetting the
internal structure of the compressed data stream. This lets the
'rsync' program take advantage of similarities in the uncompressed
input when synchronizing two files compressed with this flag. The
cost: the compressed output is usually about one percent larger.

'--suffix SUF'
'-S SUF'
Use suffix SUF instead of '.gz'. Any suffix can be given, but
suffixes other than '.z' and '.gz' should be avoided to avoid
confusion when files are transferred to other systems. A null
suffix forces gunzip to try decompression on all given files
regardless of suffix, as in:

gunzip -S "" * (*.* for MSDOS)

Previous versions of gzip used the '.z' suffix. This was changed
to avoid a conflict with 'pack'.

'--synchronous'
Use synchronous output, by transferring output data to the output
file's storage device when the file system supports this. Because
file system data can be cached, without this option if the system
crashes around the time a command like 'gzip FOO' is run the user
might lose both 'FOO' and 'FOO.gz'; this is the default with
'gzip', just as it is the default with most applications that move
data. When this option is used, 'gzip' is safer but can be
considerably slower.

'--test'
'-t'
Test. Check the compressed file integrity.

'--verbose'
'-v'
Verbose. Display the name and percentage reduction for each file
compressed.

'--version'
'-V'
Version. Display the version number and compilation options, then
quit.

'--fast'
'--best'
'-N'
Regulate the speed of compression using the specified digit N,
where '-1' or '--fast' indicates the fastest compression method
(less compression) and '--best' or '-9' indicates the slowest
compression method (optimal compression). The default compression
level is '-6' (that is, biased towards high compression at expense
of speed).

File: gzip.info, Node: Advanced usage, Next: Environment, Prev: Invoking gzip, Up: Top

4 Advanced usage
****************

Multiple compressed files can be concatenated. In this case, 'gunzip'
will extract all members at once. If one member is damaged, other
members might still be recovered after removal of the damaged member.
Better compression can be usually obtained if all members are
decompressed and then recompressed in a single step.

This is an example of concatenating 'gzip' files:

gzip -c file1 > foo.gz
gzip -c file2 >> foo.gz

Then

gunzip -c foo

is equivalent to

cat file1 file2

In case of damage to one member of a '.gz' file, other members can
still be recovered (if the damaged member is removed). However, you can
get better compression by compressing all members at once:

cat file1 file2 | gzip > foo.gz

compresses better than

gzip -c file1 file2 > foo.gz

If you want to recompress concatenated files to get better
compression, do:

zcat old.gz | gzip > new.gz

If a compressed file consists of several members, the uncompressed
size and CRC reported by the '--list' option applies to the last member
only. If you need the uncompressed size for all members, you can use:

zcat file.gz | wc -c

If you wish to create a single archive file with multiple members so
that members can later be extracted independently, use an archiver such
as 'tar' or 'zip'. GNU 'tar' supports the '-z' option to invoke 'gzip'
transparently. 'gzip' is designed as a complement to 'tar', not as a
replacement.

File: gzip.info, Node: Environment, Next: Tapes, Prev: Advanced usage, Up: Top

5 Environment
*************

The obsolescent environment variable 'GZIP' can hold a set of default
options for 'gzip'. These options are interpreted first and can be
overwritten by explicit command line parameters. As this can cause
problems when using scripts, this feature is supported only for options
that are reasonably likely to not cause too much harm, and 'gzip' warns
if it is used. This feature will be removed in a future release of
'gzip'.

You can use an alias or script instead. For example, if 'gzip' is in
the directory '/usr/bin' you can prepend '$HOME/bin' to your 'PATH' and
create an executable script '$HOME/bin/gzip' containing the following:

#! /bin/sh
export PATH=/usr/bin
exec gzip -9 "$@"

The following environment variables are applicable only when using
'gzip' on IBM Z mainframes supporting DEFLATE COMPRESSION CALL
instruction:

'DFLTCC'
Whether DEFLATE COMPRESSION CALL should be used. Default value is
'1'. Set this to '0' to disable DEFLATE COMPRESSION CALL
altogether.

'DFLTCC_LEVEL_MASK'
Compression levels on which DEFLATE COMPRESSION CALL should be
used. Represented as a bit mask in decimal or hexadecimal form,
where each bit corresponds to a compression level. Default value
is '2', which means level 1 only. In order to make use of DEFLATE
COMPRESSION CALL by default, that is, on levels 1-6, set this to
'0x7e'.

'DFLTCC_BLOCK_SIZE'
Size of deflate blocks produced by DEFLATE COMPRESSION CALL in
bytes in decimal or hexadecimal form. Default value is '1048576'
(1 megabyte). When using DEFLATE COMPRESSION CALL to compress a
file containing heterogeneous data (e.g. a '.tar' archive
containing text and binary files), setting this to a smaller value
may improve compression ratio.

'DFLTCC_FIRST_FHT_BLOCK_SIZE'
Size of the first fixed deflate block produced by DEFLATE
COMPRESSION CALL in bytes in decimal or hexadecimal form. Default
value is '4096' (4 kilobytes). When using DEFLATE COMPRESSION CALL
to compress a small file, setting this to a larger value may
improve compression ratio.

'DFLTCC_RIBM'
Value of "Reserved for IBM" field of DEFLATE COMPRESSION CALL
parameter block. Default value is '0'.

'SOURCE_DATE_EPOCH'
If set to any value, disables compression with DEFLATE COMPRESSION
CALL. This variable is normally set during reproducible builds, and
in such cases DEFLATE COMPRESSION CALL needs to be disabled,
because its output may be not reproducible.

File: gzip.info, Node: Tapes, Next: Problems, Prev: Environment, Up: Top

6 Using 'gzip' on tapes
***********************

When writing compressed data to a tape, it is generally necessary to pad
the output with zeroes up to a block boundary. When the data is read
and the whole block is passed to 'gunzip' for decompression, 'gunzip'
detects that there is extra trailing garbage after the compressed data
and emits a warning by default if the garbage contains nonzero bytes.
You can use the '--quiet' option to suppress the warning.

File: gzip.info, Node: Problems, Next: GNU Free Documentation License, Prev: Tapes, Up: Top

7 Reporting Bugs
****************

If you find a bug in 'gzip', please send electronic mail to
<bug-gzip AT gnu.org>. Include the version number, which you can find by
running 'gzip -V'. Also include in your message the hardware and
operating system, the compiler used to compile 'gzip', a description of
the bug behavior, and the input to 'gzip' that triggered the bug.

File: gzip.info, Node: GNU Free Documentation License, Next: Concept index, Prev: Problems, Up: Top

Appendix A GNU Free Documentation License
*****************************************

Version 1.3, 3 November 2008

Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.

0. PREAMBLE

The purpose of this License is to make a manual, textbook, or other
functional and useful document "free" in the sense of freedom: to
assure everyone the effective freedom to copy and redistribute it,
with or without modifying it, either commercially or
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being considered responsible for modifications made by others.

This License is a kind of "copyleft", which means that derivative
works of the document must themselves be free in the same sense.
It complements the GNU General Public License, which is a copyleft
license designed for free software.

We have designed this License in order to use it for manuals for
free software, because free software needs free documentation: a
free program should come with manuals providing the same freedoms
that the software does. But this License is not limited to
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of subject matter or whether it is published as a printed book. We
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G. Preserve in that license notice the full lists of Invariant
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I. Preserve the section Entitled "History", Preserve its Title,
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J. Preserve the network location, if any, given in the Document
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K. For any section Entitled "Acknowledgements" or "Dedications",
Preserve the Title of the section, and preserve in the section
all the substance and tone of each of the contributor
acknowledgements and/or dedications given therein.

L. Preserve all the Invariant Sections of the Document, unaltered
in their text and in their titles. Section numbers or the
equivalent are not considered part of the section titles.

M. Delete any section Entitled "Endorsements". Such a section
may not be included in the Modified Version.

N. Do not retitle any existing section to be Entitled
"Endorsements" or to conflict in title with any Invariant
Section.

O. Preserve any Warranty Disclaimers.

If the Modified Version includes new front-matter sections or
appendices that qualify as Secondary Sections and contain no
material copied from the Document, you may at your option designate
some or all of these sections as invariant. To do this, add their
titles to the list of Invariant Sections in the Modified Version's
license notice. These titles must be distinct from any other
section titles.

You may add a section Entitled "Endorsements", provided it contains
nothing but endorsements of your Modified Version by various
parties--for example, statements of peer review or that the text has
been approved by an organization as the authoritative definition of
a standard.

You may add a passage of up to five words as a Front-Cover Text,
and a passage of up to 25 words as a Back-Cover Text, to the end of
the list of Cover Texts in the Modified Version. Only one passage
of Front-Cover Text and one of Back-Cover Text may be added by (or
through arrangements made by) any one entity. If the Document
already includes a cover text for the same cover, previously added
by you or by arrangement made by the same entity you are acting on
behalf of, you may not add another; but you may replace the old
one, on explicit permission from the previous publisher that added
the old one.

The author(s) and publisher(s) of the Document do not by this
License give permission to use their names for publicity for or to
assert or imply endorsement of any Modified Version.

5. COMBINING DOCUMENTS

You may combine the Document with other documents released under
this License, under the terms defined in section 4 above for
modified versions, provided that you include in the combination all
of the Invariant Sections of all of the original documents,
unmodified, and list them all as Invariant Sections of your
combined work in its license notice, and that you preserve all
their Warranty Disclaimers.

The combined work need only contain one copy of this License, and
multiple identical Invariant Sections may be replaced with a single
copy. If there are multiple Invariant Sections with the same name
but different contents, make the title of each such section unique
by adding at the end of it, in parentheses, the name of the
original author or publisher of that section if known, or else a
unique number. Make the same adjustment to the section titles in
the list of Invariant Sections in the license notice of the
combined work.

In the combination, you must combine any sections Entitled
"History" in the various original documents, forming one section
Entitled "History"; likewise combine any sections Entitled
"Acknowledgements", and any sections Entitled "Dedications". You
must delete all sections Entitled "Endorsements."

6. COLLECTIONS OF DOCUMENTS

You may make a collection consisting of the Document and other
documents released under this License, and replace the individual
copies of this License in the various documents with a single copy
that is included in the collection, provided that you follow the
rules of this License for verbatim copying of each of the documents
in all other respects.

You may extract a single document from such a collection, and
distribute it individually under this License, provided you insert
a copy of this License into the extracted document, and follow this
License in all other respects regarding verbatim copying of that
document.

7. AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other
separate and independent documents or works, in or on a volume of a
storage or distribution medium, is called an "aggregate" if the
copyright resulting from the compilation is not used to limit the
legal rights of the compilation's users beyond what the individual
works permit. When the Document is included in an aggregate, this
License does not apply to the other works in the aggregate which
are not themselves derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these
copies of the Document, then if the Document is less than one half
of the entire aggregate, the Document's Cover Texts may be placed
on covers that bracket the Document within the aggregate, or the
electronic equivalent of covers if the Document is in electronic
form. Otherwise they must appear on printed covers that bracket
the whole aggregate.

8. TRANSLATION

Translation is considered a kind of modification, so you may
distribute translations of the Document under the terms of section
4. Replacing Invariant Sections with translations requires special
permission from their copyright holders, but you may include
translations of some or all Invariant Sections in addition to the
original versions of these Invariant Sections. You may include a
translation of this License, and all the license notices in the
Document, and any Warranty Disclaimers, provided that you also
include the original English version of this License and the
original versions of those notices and disclaimers. In case of a
disagreement between the translation and the original version of
this License or a notice or disclaimer, the original version will
prevail.

If a section in the Document is Entitled "Acknowledgements",
"Dedications", or "History", the requirement (section 4) to
Preserve its Title (section 1) will typically require changing the
actual title.

9. TERMINATION

You may not copy, modify, sublicense, or distribute the Document
except as expressly provided under this License. Any attempt
otherwise to copy, modify, sublicense, or distribute it is void,
and will automatically terminate your rights under this License.

However, if you cease all violation of this License, then your
license from a particular copyright holder is reinstated (a)
provisionally, unless and until the copyright holder explicitly and
finally terminates your license, and (b) permanently, if the
copyright holder fails to notify you of the violation by some
reasonable means prior to 60 days after the cessation.

Moreover, your license from a particular copyright holder is
reinstated permanently if the copyright holder notifies you of the
violation by some reasonable means, this is the first time you have
received notice of violation of this License (for any work) from
that copyright holder, and you cure the violation prior to 30 days
after your receipt of the notice.

Termination of your rights under this section does not terminate
the licenses of parties who have received copies or rights from you
under this License. If your rights have been terminated and not
permanently reinstated, receipt of a copy of some or all of the
same material does not give you any rights to use it.

10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of
the GNU Free Documentation License from time to time. Such new
versions will be similar in spirit to the present version, but may
differ in detail to address new problems or concerns. See
<https://www.gnu.org/copyleft/>.

Each version of the License is given a distinguishing version
number. If the Document specifies that a particular numbered
version of this License "or any later version" applies to it, you
have the option of following the terms and conditions either of
that specified version or of any later version that has been
published (not as a draft) by the Free Software Foundation. If the
Document does not specify a version number of this License, you may
choose any version ever published (not as a draft) by the Free
Software Foundation. If the Document specifies that a proxy can
decide which future versions of this License can be used, that
proxy's public statement of acceptance of a version permanently
authorizes you to choose that version for the Document.

11. RELICENSING

"Massive Multiauthor Collaboration Site" (or "MMC Site") means any
World Wide Web server that publishes copyrightable works and also
provides prominent facilities for anybody to edit those works. A
public wiki that anybody can edit is an example of such a server.
A "Massive Multiauthor Collaboration" (or "MMC") contained in the
site means any set of copyrightable works thus published on the MMC
site.

"CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0
license published by Creative Commons Corporation, a not-for-profit
corporation with a principal place of business in San Francisco,
California, as well as future copyleft versions of that license
published by that same organization.

"Incorporate" means to publish or republish a Document, in whole or
in part, as part of another Document.

An MMC is "eligible for relicensing" if it is licensed under this
License, and if all works that were first published under this
License somewhere other than this MMC, and subsequently
incorporated in whole or in part into the MMC, (1) had no cover
texts or invariant sections, and (2) were thus incorporated prior
to November 1, 2008.

The operator of an MMC Site may republish an MMC contained in the
site under CC-BY-SA on the same site at any time before August 1,
2009, provided the MMC is eligible for relicensing.

ADDENDUM: How to use this License for your documents
====================================================

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and license
notices just after the title page:

Copyright (C) YEAR YOUR NAME.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3
or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
Texts. A copy of the license is included in the section entitled ``GNU
Free Documentation License''.

If you have Invariant Sections, Front-Cover Texts and Back-Cover
Texts, replace the "with...Texts." line with this:

with the Invariant Sections being LIST THEIR TITLES, with
the Front-Cover Texts being LIST, and with the Back-Cover Texts
being LIST.

If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.

If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of free
software license, such as the GNU General Public License, to permit
their use in free software.

File: gzip.info, Node: Concept index, Prev: GNU Free Documentation License, Up: Top

Appendix B Concept index
************************

* Menu:

* bugs: Problems. (line 6)
* concatenated files: Advanced usage. (line 6)
* Environment: Environment. (line 6)
* invoking: Invoking gzip. (line 6)
* options: Invoking gzip. (line 6)
* overview: Overview. (line 6)
* sample: Sample. (line 6)
* tapes: Tapes. (line 6)

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