ustar - process tape archives
/usr/5bin/ustar -c [ bfvw ] device block filename ...
/usr/5bin/ustar -r [ bvw ] device block [ filename... ]
/usr/5bin/ustar -t [ fv ] device
/usr/5bin/ustar -u [ bvw ] device block
/usr/5bin/ustar -x [ flmovw ] device [ filename... ]
ustar is available with the System V software installation option.
Refer to for information on how to install optional software.
ustar reads and writes archive files which conform to the Ar-
chive/Interchange File Format specified in IEEE Std. 1003.1-1988.
If the files exist, their modes are not changed except as described
above. The owner, group and modification time are restored if possi-
ble. If no filename argument is given, the entire contents of the ar-
chive is extracted. Note: if several files with the same name are in
the archive, the last one will overwrite all earlier ones.
-c Create a new archive; writing begins at the beginning of the ar-
chive, instead of after the last file.
-r Write names files to the end of the archive.
-t List the names of all of the files in the archive.
-u Add named files to the archive if they are not already there, or
if they have been modified since last written into the archive.
This implies the -r option.
-x Extracts 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 does not exist on the system, the file is create with
the same mode as the one in the archive, except that the set-
user-id and get-group-id modes are not set unless the user has
-b Use the next argument on the command line as the blocking factor
for tape records. The default is 1; the maximum is 20. This
option should only be used with raw magnetic tape archives.
Normally, the block size is determined automatically when read-
-f Use the next argument on the command line as the name of the ar-
chive instead of the default, which is usually a tape drive. If
`-' is specified as a filename ustar writes to the standard out-
put or reads from the standard input, whichever is appropriate
for the options given. Thus, ustar can be used as the head or
tail of a pipeline.
-l Report if ustar cannot resolve all of the links to the files
being archived. If -l is not specified, no error messages are
written to the standard output. This modifier is only valid
with the -c, -r and -u options.
-m Do not restore the modification times. The modification time of
the file will be the time of extraction. This modifier is
invalid with the -t option.
-o Extracted files take on the user and group identifier of the
user running the program rather than those on the archive. This
modifier is only valid with the -x option.
-v Verbose. Print the name of each file it processes, preceded by
the option letter. With the -t option, -v gives more informa-
tion about the archive entries than just the name.
-w Print the action to be taken, followed by the name of the file,
and then wait for the user's confirmation. If a word beginning
with y is given, the action is performed. Any other input
implies no and the action is not performed. This modifier is
invalid with the -t option.
/dev/tty used to prompt the user for information when the -i
or -y options are specified
cpio(1), dd(1), find(1), pax(1V), paxcpio(1V), cpio(5), tar(5)
Mark H. Colburn
117 Mackubin Street, Suite 1
St. Paul, MN 55102
Sponsored by The USENIX Association for public distribution.
6 September 1989 USTAR(1V)