tar(1) UNIX System V(Essential Utilities) tar(1)
NAME
tar - tape file archiver
SYNOPSIS
/usr/sbin/tar -c[vwfbLkFhienAC[#s]] device block files tapesize incfile . . .
/usr/sbin/tar -c[vwfbLkXhienAC[#s]] device block files tapesize excfile . . .
/usr/sbin/tar -r[vwfbLkFhienAC[#s]] device block files tapesize incfile . . .
/usr/sbin/tar -r[vwfbLkXhienAC[#s]] device block files tapesize excfile . . .
/usr/sbin/tar -t[vfLXien[#s] device [files . . .] excfile
/usr/sbin/tar -u[vwfbLkXhienAC[#s]] device block files tapesize excfile . . .
/usr/sbin/tar -u[vwfbLkFhienAC[#s]] device block files tapesize incfile . . .
/usr/sbin/tar -x[lmovwfLXpienAC[#s]] device [files .
DESCRIPTION
tar saves and restores files on magnetic tape. Its actions are
controlled by a string of characters containing one option (c, r, t, u,
or x), and possibly followed by one or more modifiers (v, w, f, b, L, k,
F, X, h, i, e, n, A, l, m, o, p, and #s). Other arguments to the command
are files (or directory names) specifying which files are to be dumped or
restored. In all cases, appearance of a directory name refers to the
files and (recursively) subdirectories of that directory.
The options are as follows:
-c Create a new tape; writing begins at the beginning of the tape,
instead of after the last file. The -c option implies the -r
option.
-r Replace. The named files are written on the end of the tape.
The -c and -u options imply the -r option.
-t Table. The names and other information for the specified files
are listed each time that they occur on the tape. The listing is
similar to the format produced by the ls -l command [see ls(1)].
If no files argument is given, all the names on the tape are
listed.
-u Update. The named files are added to the tape if they are not
already there, or have been modified since last written on that
tape. The -u option implies the -r option.
-x Extract. The named files are extracted from the tape. If a
named file matches a directory whose contents had been written
onto the tape, this directory is (recursively) extracted. Use
the file or directory's relative path when appropriate, or tar
will not find a match. The owner, modification time, and mode
are restored (if possible). If no files argument is given, the
entire contents of the tape is extracted. Note that if several
files with the same name are on the tape, the last one overwrites
all earlier ones.
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tar(1) UNIX System V(Essential Utilities) tar(1)
The modifiers below may be used in the order shown in the synopsis.
#s This modifier determines the drive on which the tape is mounted
(replace # with the drive number) and the speed of the drive
(replace s with l, m, or h for low, medium or high). The
modifier tells tar to use a drive other than the default drive,
or the drive specified with the -f modifier. The defaults are
listed in /etc/default/tar.
v Verbose. Normally, tar does its work silently. The v (verbose)
modifier causes it to print the name of each file it treats,
preceded by the option. With the -t option, v gives more
information about the tape entries than just the name.
w What. This modifier causes tar to print the action to be taken,
followed by the name of the file, and then wait for your
confirmation. If a word beginning with y is given, the action is
performed. Any other input means no. This is not valid with the
-t option.
f File. This causes tar to use the device argument as the name of
the archive instead of the default. If the name of the file is
-, tar writes to the standard output or reads from the standard
input, whichever is appropriate. Thus, tar can be used as the
head or tail of a pipeline. tar can also be used to move
hierarchies with the command:
cd fromdir; tar cf - . | (cd todir; tar xf -)
b Blocking Factor. This modifier causes tar to use the block
argument as the blocking factor for tape records. The default is
20. This modifier should not be supplied when operating on
regular archives or block special devices. It is mandatory
however, when reading archives on raw magnetic tape archives (see
f above). The block size is determined automatically when
reading tapes created on block special devices (options x and t).
l Link. This modifier causes tar to complain if it cannot resolve
all of the links to the files being dumped. If the l modifier is
not specified, no error messages are printed.
m Modify. This modifier causes tar to not restore the modification
times. The modification time of the file will be the time of
extraction.
o Ownership. This modifier causes extracted files to take on the
user and group identifier of the user running the program, rather
than those on tape. This is only valid with the -x option.
L Follow symbolic links. This modifier causes symbolic links to be
followed. By default, symbolic links are not followed.
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tar(1) UNIX System V(Essential Utilities) tar(1)
k This modifier uses the tapesize argument as the size in bytes per
volume for non-tape devices (such as a floppy drive). A value of
0 for tapesize causes multi-volume mode to be disabled
(interpreted as an infinite volume size). This modifier may be
used with the -c, -r, and -u options.
F This modifier uses the incfile argument as a file containing a
list of named files (or directories) to be included on the tape.
This modifier may only be used with the -c, -r, and -u options.
This modifier may not be used with the X modifier.
X This modifier uses the excfile argument as a file containing a
list of named files (or directories) to be excluded. This
modifier may not be used with the F modifier.
h This modifier causes tar to follow symbolic links as if they were
normal files or directories. Normally tar does not follow
symbolic links. The h modifier may be used with the -c, -r, and
-u options.
p This modifier restores the named file arguments to their original
modes, ignoring the present value returned by umask [see umask(2)
in the Programmer's Reference Manual]. setuid and sticky bit
information are also restored if the effective user ID is root.
This modifier may only be used with the -x option.
i This modifier causes tar to ignore directory checksum errors.
e This modifier causes tar to quit when certain minor errors are
encountered. Otherwise tar will continue when minor errors are
encountered.
n This modifier must be used when the device argument is for a
non-tape device (for example, a floppy drive).
A This modifier causes absolute pathnames for files to be
suppressed, and may be used with the -r, -c, -u, and -x options.
This causes all pathnames to be interpreted as relative to the
current working directory.
C This modifier, on output, sets a flag indicating that all regular
files are compressed. On input, this modifier sets a flag to
decompress all regular files.
FILES
/etc/default/tar
/tmp/tar*
/usr/lib/locale/locale/LCMESSAGES/uxcore
language-specific message file [See LANG on environ(5).]
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tar(1) UNIX System V(Essential Utilities) tar(1)
SEE ALSO
ar(1), cpio(1), ls(1).
umask(2) in the Programmer's Reference Manual.
DIAGNOSTICS
Complains about tape read/write errors.
Complains if insufficient memory is available to hold the link tables.
NOTES
There is no way to ask for the n-th occurrence of a file.
The -b modifier should not be used with archives that are going to be
updated. The current magnetic tape driver cannot backspace raw magnetic
tape. If the archive is on a disk file, the -b modifier should not be
used at all, because updating an archive stored on disk can destroy it.
The current limit on file name length is 100 characters.
You cannot restore a mulit-level archive created with UNIX System V
Release 4 tar on a pre-Release 4 system. A false warning message that
file permissions have changed will be issued.
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