(version @value{VERSION}, @value{UPDATED}),
and documents commands for compressing and decompressing data.
-Copyright @copyright{} 1998-1999, 2001-2002, 2006-2007, 2009-2016 Free Software
+Copyright @copyright{} 1998-1999, 2001-2002, 2006-2007, 2009-2018 Free Software
Foundation, Inc.
Copyright @copyright{} 1992, 1993 Jean-loup Gailly
@command{gzip} reduces the size of the named files using Lempel--Ziv coding
(LZ77). Whenever possible, each file is replaced by one with the
extension @samp{.gz}, while keeping the same ownership modes, access and
-modification times. (The default extension is @samp{-gz} for @abbr{VMS},
+modification times. (The default extension is
@samp{z} for @abbr{MSDOS}, @abbr{OS/2} @abbr{FAT} and Atari.)
If no files are specified or
if a file name is @file{-}, the standard input is compressed to the standard
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, @command{gzip} keeps the original file name and time stamp in
-the compressed file. These are used when decompressing the file with the
-@option{-N} option. This is useful when the compressed file name was
-truncated or when the time stamp was not preserved after a file
-transfer. However, due to limitations in the current @command{gzip} file
-format, fractional seconds are discarded. Also, time stamps must fall
-within the range 1970-01-01 00:00:00 through 2106-02-07 06:28:15
-@abbr{UTC}, and hosts whose operating systems use 32-bit time
-stamps are further restricted to time stamps no later than 2038-01-19
+By default, @command{gzip} keeps the original file name in the
+compressed file. This can be useful when decompressing the file with
+@option{-N} if the compressed file name was truncated after a file
+transfer.
+
+If the original is a regular file, @command{gzip} by default keeps its
+timestamp in the compressed file. This can be useful when
+decompressing the file with @option{-N} if the timestamp was not
+preserved after a file transfer.
+However, due to limitations in the current @command{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
+@abbr{UTC}, and hosts whose operating systems use 32-bit timestamps
+are further restricted to timestamps no later than 2038-01-19
03:14:07 @abbr{UTC}. The upper bounds assume the typical case
where leap seconds are ignored.
the @command{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. @command{gzip} normally preserves the mode,
-ownership and time stamps of files when compressing or decompressing.
+ownership and timestamps of files when compressing or decompressing.
The @command{gzip} file format is specified in P. Deutsch, GZIP file
format specification version 4.3,
-@uref{http://www.ietf.org/rfc/rfc1952.txt, Internet @abbr{RFC} 1952} (May
+@uref{https://www.ietf.org/rfc/rfc1952.txt, Internet @abbr{RFC} 1952} (May
1996). The @command{zip} deflation format is specified in P. Deutsch,
DEFLATE Compressed Data Format Specification version 1.3,
-@uref{http://www.ietf.org/rfc/rfc1951.txt, Internet @abbr{RFC} 1951} (May
+@uref{https://www.ietf.org/rfc/rfc1951.txt, Internet @abbr{RFC} 1951} (May
1996).
@node Sample
-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 time stamp
- -N, --name save or restore the original name and time stamp
+ -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
@example
method: compression method (deflate,compress,lzh,pack)
crc: the 32-bit CRC of the uncompressed data
-date & time: time stamp for the uncompressed file
+date & time: timestamp for the uncompressed file
@end example
The @abbr{CRC} is given as ffffffff for a file not in gzip format.
@item --no-name
@itemx -n
-When compressing, do not save the original file name and time stamp by
+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 @command{gzip}
suffix from the compressed file name) and do not restore the original
-time stamp if present (copy it from the compressed file). This option
+timestamp if present (copy it from the compressed file). This option
is the default when decompressing.
@item --name
@itemx -N
-When compressing, always save the original file name and time stamp; this
+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
-time stamp if present. This option is useful on systems which have
-a limit on file name length or when the time stamp has been lost after
+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.
@item --quiet
exec gzip -9 "$@@"
@end example
-On @abbr{VMS}, the name of the obsolescent environment variable is
-@env{GZIP_OPT}, to avoid a conflict with the symbol set for invocation
-of the program.
-
@node Tapes
@chapter Using @command{gzip} on tapes
@cindex tapes