TAR(1)                               BSD                                TAR(1)



NAME
     tar - tape archiver

SYNOPSIS
     tar [ key ] [ name ... ]

DESCRIPTION
     tar saves and restores multiple files on a single file (usually a
     magnetic tape, but it can be any file). The key argument is a string of
     characters containing at most one function letter and possibly one or
     more function modifiers.  Other arguments to tar are file or directory
     names specifying which files to dump or restore.  In all cases,
     appearance of a directory name refers to the files and (recursively)
     subdirectories of that directory.

FUNCTIONS
     c       Create a new tape; writing begins on the beginning of the tape
             instead of after the last file.  This command implies r.

     r       Write the named files on the end of the tape.  The c function
             implies this.

     u       Add the named files to the tape if they are not already there or
             have been modified since last put on the tape.

     x       Extract the named files are extracted from the tape.  If the
             named file matches a directory whose contents have been written
             onto the tape, this directory is (recursively) extracted.  The
             owner, modification time, and mode are restored (if possible).
             If no file argument is given, the entire content of the tape is
             extracted.  Note that if multiple entries specifying the same
             file are on the tape, the last one overwrites all earlier copies.
             tar writes restored files to the current directory.

     t       The names of the specified files are listed each time they occur
             on the tape.  If no file argument is given, all of the names on
             the tape are listed.

OPTIONS
     Unlike function specifiers, option flags must be immediately preceded by
     a dash (-).

     0, ..., 9 Select an alternate drive on which the tape is mounted.  The
               default is drive 0 at 1600 bpi, which is normally /dev/rmt8.

     B         Force input and output blocking to 20 blocks per record.  This
               option allows tar to work across a communications channel where
               the blocking may not be maintained.

     b factor  Use factor as the blocking factor for tape records. The default
               is 20 (the maximum). This option should be used only with raw
               magnetic tape archives. tar automatically determines block size
               when reading tapes (with functions x and t).




     C dir     perform a chdir(2) to the filename preceded by this option.
               This option allows multiple directories not related by a close
               common parent to be archived using short relative path names.
               For example, to archive files from /usr/include and from /etc,

               you might use
                    tar c -C /usr include -C
               Previous restrictions dealing with tar's inability to properly
               handle blocked archives have been lifted.

     f archive Use archive as the name of the archive instead of /dev/rmt?.
               If you give a dash (-) as the name of the file, tar writes to
               standard output or reads from standard input as appropriate.
               You can use tar to move hierarchies with the command
                    cd fromdir; tar cf - . | (cd todir; tar xf -)

     h         Force tar to follow symbolic links as if they were normal files
               or directories.  Normally tar does not follow symbolic links.

     l         Complain if tar cannot resolve all of the links to the files
               dumped.

     m         Do not restore the modification times.  The modification time
               is set to the time of extraction.

     o         Suppress writing of owner and permission information from
               archived directories.

     p         Restore files to their original modes, ignoring the present
               umask(2).  Restores setuid to the super-user.

     v         Use verbose mode.  Normally tar does its work silently.  This
               option makes tar print the name of each file it treats preceded
               by the function letter.  With the t function, the verbose
               option gives more information about the tape entries than just
               their names.

     w         Print the action to be taken followed by filename, then wait
               for user confirmation. If you enter a word beginning with "y",
               tar does the action. Any other input means "no".

     A         Include Apollo-specific information; this option allows tar to
               handle Domain/OS typed files.

NOTES
     Cartridge tapes must be rewound with the command mt rewind.

FILES
     /dev/rmt?
     /tmp/tar*



DIAGNOSTICS
     Complains about bad key characters and tape read/write errors.
     Complains if not enough memory is available to hold the link tables.

BUGS
     There is no way to ask for the nth occurrence of a file.
     Tape errors are handled ungracefully.
     The u option can be slow.
     The current limit on filename length is 100 characters.
     There is no way to follow symbolic links selectively.
     When you extract files created with the r or u options, directory
     modification times may not be set correctly.

SEE ALSO
     mt(1), rbak(1), wbak(1), rwmt(1), tar(5)