tar |
{crtux}[014578beFfHhjLmNOoPpqsvwXZz]
[blocking-factor | format | archive | replstr]
[-C directory]
[-I file]
[file ...] |
tar |
{-crtux}
[-014578eHhjLmNOoPpqvwXZz]
[-b blocking-factor]
[-C directory]
[-F format]
[-f archive]
[-I file]
[-s replstr]
[file ...] |
The tar command creates, adds files to, or
extracts files from an archive file in “tar” format. A tar
archive is often stored on a magnetic tape, but can be stored equally well
on a floppy, CD-ROM, or in a regular disk file.
In the first (legacy) form, all option flags except for
-C and -I must be contained
within the first argument to tar and must not be
prefixed by a hyphen (‘-’). Option arguments, if any, are
processed as subsequent arguments to tar and are
processed in the order in which their corresponding option flags have been
presented on the command line.
In the second and preferred form, option flags may be given in any
order and are immediately followed by their corresponding option argument
values.
One of the following flags must be present:
-c- Create new archive, or overwrite an existing archive, adding the specified
files to it.
-r- Append the named new files to existing archive. Note that this will only
work on media on which an end-of-file mark can be overwritten.
-t- List contents of archive. If any files are named on the command line, only
those files will be listed. The file arguments may
be specified as glob patterns (see
glob(7) for
more information), in which case
tar will list all
archive members that match each pattern.
-u- Alias for
-r.
-x- Extract files from archive. If any files are named on the command line,
only those files will be extracted from the archive. The
file arguments may be specified as glob patterns
(see glob(7)
for more information), in which case
tar will
extract all archive members that match each pattern.
If more than one copy of a file exists in the archive, later
copies will overwrite earlier copies during extraction. The file mode
and modification time are preserved if possible. The file mode is
subject to modification by the
umask(2).
In addition to the flags mentioned above, any of the following
flags may be used:
-b
blocking-factor- Set blocking factor to use for the archive.
tar
uses 512-byte blocks. The default is 20, the maximum is 126. Archives with
a blocking factor larger than 63 violate the POSIX standard and will not
be portable to all systems.
-C
directory- This is a positional argument which sets the working directory for the
following files. When extracting, files will be extracted into the
specified directory; when creating, the specified files will be matched
from the directory.
-e- Stop after the first error.
-F
format- Specify the output archive format, with the default format being
pax. tar currently
supports the following formats:
bcpio- The old binary cpio format. The default blocksize for this format is
5120 bytes. This format is not very portable and should not be used
when other formats are available. Inode and device information about a
file (used for detecting file hard links by this format), which may be
truncated by this format, is detected by
tar
and is repaired.
cpio- The extended cpio interchange format specified in the
IEEE Std 1003.2 (“POSIX.2”)
standard. The default blocksize for this format is 5120 bytes. Inode
and device information about a file (used for detecting file hard
links by this format), which may be truncated by this format, is
detected by
tar and is repaired.
sv4cpio- The System V release 4 cpio. The default blocksize for this format is
5120 bytes. Inode and device information about a file (used for
detecting file hard links by this format), which may be truncated by
this format, is detected by
tar and is
repaired.
sv4crc- The System V release 4 cpio with file CRC checksums. The default
blocksize for this format is 5120 bytes. Inode and device information
about a file (used for detecting file hard links by this format),
which may be truncated by this format, is detected by
tar and is repaired.
tar- The old BSD tar format as found in
4.3BSD. The default blocksize for this format
is 10240 bytes. Pathnames stored by this format must be 100 characters
or less in length. Only regular files, hard links, soft links, and
directories will be archived (other file system types are not
supported). For backwards compatibility with even older tar formats,
see the description for
-o.
ustar- The extended tar interchange format specified in the
IEEE Std 1003.2 (“POSIX.2”)
standard. The default blocksize for this format is 10240 bytes.
Filenames stored by this format must be 100 characters or less in
length; the total pathname must be 256 characters or less.
pax- The pax interchange format specified in the IEEE Std
1003.1-2001 (“POSIX.1”) standard. The default
blocksize for this format is 5120 bytes.
tar will detect and report any file
that it is unable to store or extract as the result of any specific
archive format restrictions. The individual archive formats may impose
additional restrictions on use. Typical archive format restrictions
include (but are not limited to): file pathname length, file size, link
pathname length, and the type of the file.
-f
archive- Read from or write to archive. A hyphen (-) can be
used to represent standard input or output. The default is
/dev/rst0. See also the
TAPE environment variable.
-H- Follow symlinks given on the command line only.
-h- Follow symbolic links as if they were normal files or directories. In
extract mode this means that a directory entry in the archive will not
overwrite an existing symbolic link, but rather what the link ultimately
points to.
-I
file- This is a positional argument which reads the names of files to archive or
extract from the given file, one per line.
-j- Compress archive using bzip2. The bzip2 utility must be installed
separately.
-L- Synonym for the
-h option.
-m- Do not preserve modification time.
-N- Use only the numeric UID and GID values when creating or extracting an
archive.
-O- Write old-style (non-POSIX) archives.
-o- Don't write directory information that the older (V7) style
tar is unable to decode. This implies the
-O flag.
-P- Do not strip leading slashes (‘/’) from pathnames. The
default is to strip leading slashes.
-p- Preserve user and group ID as well as file mode regardless of the current
umask(2).
The setuid and setgid bits are only preserved if the user and group ID
could be preserved. Only meaningful in conjunction with the
-x flag.
-q- Select the first archive member that matches each
file operand. No more than one archive member is
matched for each file. When members of type
directory are matched, the file hierarchy rooted at that directory is also
matched.
-s
replstr- Modify the archive member names according to the substitution expression
replstr, using the syntax of the
ed(1) utility
regular expressions. file arguments may be given to
restrict the list of archive members to those specified.
The format of these regular expressions is
/old/new/[gp]
As in ed(1), old is a basic regular expression
(see re_format(7)) and new can contain an
ampersand (‘&’),
‘\n’ (where
n is a digit) back-references, or subexpression
matching. The old string may also contain newline
characters. Any non-null character can be used as a delimiter
(‘/’ is shown here). Multiple
-s expressions can be specified. The expressions
are applied in the order they are specified on the command line,
terminating with the first successful substitution.
The optional trailing g continues to
apply the substitution expression to the pathname substring, which
starts with the first character following the end of the last successful
substitution. The first unsuccessful substitution stops the operation of
the g option. The optional trailing
p will cause the final result of a successful
substitution to be written to standard error in the following
format:
File or archive member names that substitute to the empty
string are not selected and will be skipped.
-v- Verbose operation mode. If
-v is specified
multiple times or if the -t option is also
specified, tar will use a long format for listing
files, similar to ls(1) -l.
-w- Interactively rename files. This option causes
tar
to prompt the user for the filename to use when storing or extracting
files in an archive.
-X- Do not cross mount points in the file system.
-Z- Compress archive using
compress(1).
-z- Compress archive using gzip(1).
The options [-014578] can be used to
select one of the compiled-in backup devices,
/dev/rstN.
TMPDIR- Path in which to store temporary files.
TAPE- Default tape device to use instead of /dev/rst0.
If set to hyphen (‘-’), standard output is used.
- /dev/rst0
- default archive name
The tar utility exits with one of the
following values:
- 0
- All files were processed successfully.
- 1
- An error occurred.
Create an archive on the default tape drive, containing the files
named bonvole and sekve:
$ tar c bonvole sekve
Create a gzip(1) compressed archive, called
foriru.tar.gz, containing the files
bonvole and sekve:
$ tar czf foriru.tar.gz bonvole
sekve
Verbosely create an archive, called
backup.tar.gz, of all files matching the shell
glob(7)
function *.c:
$ tar cvzf backup.tar.gz
*.c
Verbosely list, but do not extract, all files ending in
.jpeg from a compressed archive named
backup.tar.gz. Note that the glob pattern has been
quoted to avoid expansion by the shell:
$ tar tvzf backup.tar.gz
'*.jpeg'
Verbosely extract an archive, called
foo.tar.gz, to the directory
/var/foo:
$ tar xvzf foo.tar.gz -C
/var/foo
For more detailed examples, see
pax(1).
Whenever tar cannot create a file or a
link when extracting an archive or cannot find a file while writing an
archive, or cannot preserve the user ID, group ID, file mode, or access and
modification times when the -p option is specified,
a diagnostic message is written to standard error and a non-zero exit value
will be returned, but processing will continue. In the case where
tar cannot create a link to a file,
tar will not create a second copy of the file.
If the extraction of a file from an archive is prematurely
terminated by a signal or error, tar may have only
partially extracted the file the user wanted. Additionally, the file modes
of extracted files and directories may have incorrect file bits, and the
modification and access times may be wrong.
If the creation of an archive is prematurely terminated by a
signal or error, tar may have only partially created
the archive, which may violate the specific archive format
specification.
A tar command first appeared in
Version 7 AT&T UNIX.
Keith Muller at the University of
California, San Diego.
The -j and -L
flags are not portable to other versions of tar
where they may have a different meaning.