[Previous] [Contents] [Next]

tar

Read and write tape archive files (UNIX)

Syntax:

Create a new archive:

   tar -c [-b blocking] [-f file] [-vw] [filename...]

Write named files to the end of an archive:

   tar -r -f file [-b blocking] [-vw] [filename...]

List all the files contained in an archive:

   tar -t [-f file] [-v] [filename]

Extract named files from an archive:

   tar -x [-f file] [-lmovw] [filename...]

Options:

-b blocking
Specify the blocking factor for tape records. The default is 1. This option should be used only with raw magnetic tape archives.
-c
Create a new archive. Writing begins at the beginning of the archive, instead of after the last file.
-f file
Specify the name of the archive to use instead of the default, which is standard output. If the dash character (-) is specified as a filename, tar writes to the standard output or reads from the standard input, whichever is appropriate for the options given. Thus, tar can be used as the head or tail of a pipeline.
-l
("el") Report if all of the links to the files being archived cannot be resolved. If this option isn't specified, no error messages are written to the standard output. This option is valid only with the -c and -r options.
-m
Don't restore modification times. The modification time of the file will be the time of extraction. This option is invalid with the -t option.
-o
Cause extracted files to take on the user and group identifier of the user running the program rather than those on the archive. This option is valid only with the -x option.
-r
Write named files to the end of the archive specified in the required -f file option.
-t
List the names of all of the files in the archive.
-v
Be verbose. Usually, tar works silently, but the -v option causes it to print the name of each file it processes, preceded by the option letter. With the -t option, -v gives more information about the archive entries than just the name.
-w
Print the action to be taken, followed by the name of the file, then wait for the user's confirmation. If you enter a word beginning with y, the action is performed. Any other input means "no". This option is invalid with the -t option.
-x
Extract named files from the archive. If a named file matches a directory whose contents had been written onto the archive, that directory is recursively extracted. If a named file in the archive doesn't exist on the system, the file is created with the same mode as the one in the archive, except that the set-user-id and set-group-id modes are set only if you have appropriate privileges.

If the files exist, their modes are not changed except as described above. The owner, group, and modification time are restored if possible. If no filename argument is given, the entire contents of the archive is extracted. Note that if several files with the same name are in the archive, the last one will overwrite all earlier ones.

filename
The pathname of the file to be archived.

Description:

The tar utility reads and writes archive files that conform to the Archive/Interchange File Format specified in POSIX Std/1003.1-1988.

Examples:

Display a verbose listing of the archive members in dist.tar:

    tar -tvf dist.tar

Copy the contents of the current directory to the floppy drive:

    tar -cf /dev/fd0 .

Make an archive, backup.tar, of all the C source and header files in the current directory:

    tar -cvf backup.tar *.[ch]

Files:

The controlling terminal (/dev/tty) is used to prompt the user for information when either or both the -i or -y options are specified.

See also:

cpio, pax, scsi_util, tape


[Previous] [Contents] [Next]