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TAR(1)                  FreeBSD General Commands Manual                 TAR(1)

     tar -- tape archiver; manipulate "tar" archive files

     tar [[-]bundled-options Args] [gnu-style-flags]
         [filenames | -C directory-name] ...

     Tar is short for ``tape archiver'', so named for historical reasons; the
     tar program creates, adds files to, or extracts files from an archive
     file in tar format, called a tarfile.  A tarfile is often a magnetic
     tape, but can be a floppy diskette or any regular disk file.

     The first argument word of the tar command line is usually a command word
     of bundled function and modifier letters, optionally preceded by a dash;
     it must contain exactly one function letter from the set A, c, d, r, t,
     u, x, for append, create, difference, replace, table of contents, update,
     and extract (further described below).  The command word can also contain
     other function modifiers described below, some of which will take argu-
     ments from the command line in the order they are specified in the com-
     mand word (review the EXAMPLES section).  Functions and function modi-
     fiers can also be specified with the GNU argument convention (preceded by
     two dashes, one function or modifier per word.  Command-line arguments
     that specify files to add to, extract from, or list from an archive may
     be given as shell pattern matching strings.

     Exactly one of the following functions must be specified.

     --concatenate  Append the contents of named file, which must itself be a
                    tar archive, to the end of the archive (erasing the old
                    end-of-archive block).  This has the effect of adding the
                    files contained in the named file to the first archive,
                    rather than adding the second archive as an element of the
                    first.  Note: This option requires a rewritable tarfile,
                    and therefore does not work on quarter-inch cartridge
     --create       Create a new archive (or truncates an old one) and writes
                    the named files to it.
     --compare      Find differences between files in the archive and corre-
                    sponding files in the file system.
     --delete       Delete named files from the archive.  (Does not work on
                    quarter-inch tapes).
     --append       Append files to the end of an archive.  (Does not work on
                    quarter-inch tapes).
     --list         List the contents of an archive; if filename arguments are
                    given, only those files are listed, otherwise the entire
                    table of contents is listed.
     --update       Append the named files if the on-disk version has a modi-
                    fication date more recent than their copy in the archive
                    (if any).  Does not work on quarter-inch tapes.
     --get          Extract files from an archive.  The owner, modification
                    time, and file permissions are restored, if possible.  If
                    no file arguments are given, extract all the files in the
                    archive.  If a filename argument matches the name of a
                    directory on the tape, that directory and its contents are
                    extracted (as well as all directories under that direc-
                    tory).  If the archive contains multiple entries corre-
                    sponding to the same file (see the --append command
                    above), the last one extracted will overwrite all earlier

     The other options to tar may be combined arbitrarily; single-letter
     options may be bundled in with the command word.  Verbose options which
     take arguments will be followed by the argument; single-letter options
     will consume successive command line arguments (see the EXAMPLES below).

     --help                  Prints a message listing and briefly describing
                             all the command options to tar.
     --atime-preserve        Restore the access times on files which are writ-
                             ten to tape (note that this will change the
                             inode-change time!).
     --block-size number     Sets the block size for reading or writing to
                             number * 512-byte blocks.
     --read-full-blocks      Re-assemble short reads into full blocks (for
                             reading 4.2BSD pipes).
     -C directory
     --directory directory   Change to directory before processing the remain-
                             ing arguments.
     --checkpoint            Print number of buffer reads/writes while read-
                             ing/writing the archive.
     -f [hostname:]file
     --file [hostname:]file  Read or write the specified file (default is
                             /dev/sa0).  If a hostname is specified, tar will
                             use rmt(8) to read or write the specified file on
                             a remote machine.  ``-'' may be used as a file-
                             name, for reading or writing to/from stdin/std-
     --force-local           Archive file is local even if it has a colon.
     -F file
     --info-script file
     --new-volume-script file
                             Run a script at the end of each archive volume
                             (implies -M).
     --fast-read             Stop after all non-wildcard extraction targets
                             have been found in the archive.
     --incremental           Create/list/extract old GNU-format incremental
     -g file
     --listed-incremental file
                             Create/list/extract new GNU-format incremental
     --dereference           Don't write symlinks as symlinks; write the data
                             of the files they name.
     --ignore-zeros          Ignore blocks of zeroes in archive (usually means
     --ignore-failed-read    Don't exit with non-zero status on unreadable
     --bunzip2               Filter the archive through bzip2(1).
     --keep-old-files        Keep files which already exist on disk; don't
                             overwrite them from the archive.
     -K file
     --starting-file file    Begin at file in the archive.
     --one-file-system       Stay in local file system when creating an ar-
                             chive (do not cross mount points).
     -L number
     --tape-length number    Change tapes after writing number * 1024 bytes.
     --modification-time     Don't extract file modified time.
     --multi-volume          Create/list/extract multi-volume archive.
     --norecurse             Don't recurse into subdirectories when creating.
     --volno-file file       File name with volume number to start with.
     -N date
     --after-date date
     --newer date            Only store files with creation time newer than
     --newer-mtime date      Only store files with modification time newer
                             than date.
     --portability           Write a V7 format archive, rather than POSIX for-
     --to-stdout             Extract files to standard output.
     --preserve-permissions  Extract all protection information.
     --preserve              Has the effect of -p -s.
     --absolute-paths        Don't strip leading `/' from file names.
     --record-number         Show record number within archive with each mes-
     --remove-files          Remove files after adding them to the archive.
     --preserve-order        List of names to extract is sorted to match ar-
     --show-omitted-dirs     Show directories which were omitted while pro-
                             cessing the archive.
     --sparse                Handle ``sparse'' files efficiently.
     -T file
     -I file
     --files-from file       Get names of files to extract or create from
                             file, one per line.
     --null                  Modifies behavior of -T to expect null-terminated
                             names; disables -C.
     --totals                Prints total bytes written with --create.
     --unlink-first          Unlink files before creating them.
     --verbose               Lists files written to archive with --create or
                             extracted with --extract; lists file protection
                             information along with file names with --list.
     -V volume-name
     --label volume-name     Create archive with the given volume-name.
     --version               Print tar program version number.
     --confirmation          Ask for confirmation for every action.
     --verify                Attempt to verify the archive after writing it.
     --exclude pattern       Exclude files matching the pattern (don't extract
                             them, don't add them, don't list them).
     -X file
     --exclude-from file     Exclude files listed in file.
     --uncompress            Filter the archive through compress(1).
     --gunzip                Filter the archive through gzip(1).
     --use-compress-program program
                             Filter the archive through program (which must
                             accept -d to mean ``decompress'').
     --block-compress        Block the output of compression program for tapes
                             or floppies (otherwise writes will be of odd
                             length, which device drivers may reject).
     -[0-7][lmh]             Specify tape drive and density.

     The environment variable TAR_OPTIONS can hold a set of default options
     for tar.  These options are interpreted first and can be overwritten by
     explicit command line parameters.

     To create an archive on tape drive /dev/sa0 with a block size of 20
     blocks, containing files named bert and ernie, you can enter
           tar cfb /dev/sa0 20 bert ernie
           tar --create --file /dev/sa0 --block-size 20 bert ernie
     Note that the -f and -b flags both require arguments, which they take
     from the command line in the order they were listed in the command word.

     Because /dev/sa0 is the default device, and 20 is the default block size,
     the above example could have simply been
           tar c bert ernie

     To extract all the C sources and headers from an archive named
     backup.tar, type
           tar xf backup.tar '*.[ch]'
     Note that the pattern must be quoted to prevent the shell from attempting
     to expand it according the files in the current working directory (the
     shell does not have access to the list of files in the archive, of

     To move file hierarchies, use a command line like this:

     tar -cf - -C srcdir . | tar xpf - -C destdir

     To create a compressed archive on diskette, using gzip(1), use a command-
     line like
           tar --block-compress -z -c -v -f /dev/fd1a -b 36 tar/

     Note that you cannot mix bundled flags and --style flags; you can use
     single-letter flags in the manner above, rather than having to type
           tar --block-compress --gzip --verbose --file /dev/fd1a --block-size
           20 tar/

     The above-created diskette can be listed with
           tar tvfbz /dev/fd1a 36

     To join two tar archives into a single archive, use
           tar Af archive1.tar archive2.tar
     which will add the files contained in archive2.tar onto the end of
     archive1.tar (note that this can't be done by simply typing
           cat archive2.tar >> archive1.tar
     because of the end-of-file block at the end of a tar archive).

     To archive all files from the directory srcdir, which were modified after
     Feb. 9th 1997, 13:00 h, use
           tar -c -f backup.tar --newer-mtime 'Feb 9 13:15 1997' srcdir/

     Other possible time specifications are `02/09/97 13:15', `1997-02-09
     13:15', `13:15 9 Feb 1997', `9 Feb 1997 13:15', `Feb. 9, 1997 1:15pm',
     `09-Feb', `3 weeks ago' or `May first Sunday'.  To specify the correct
     time zone use either e.g. `13:15 CEST' or `13:15+200'.

     The tar program examines the following environment variables.

     POSIXLY_CORRECT  Normally, tar will process flag arguments that appear in
                      the file list.  If set in the environment, this causes
                      tar to consider the first non-flag argument to terminate
                      flag processing, as per the POSIX specification.

     SHELL            In interactive mode, a permissible response to the
                      prompt is to request to spawn a subshell, which will be
                      /bin/sh unless the SHELL variable is set.

     TAPE             Changes tar's default tape drive (which is still over-
                      ridden by the -f flag).

     TAR_RSH          The TAR_RSH environment variable allows you to override
                      the default shell used as the transport for tar.

     /dev/sa0  The default tape drive.

     The -y is a FreeBSD localism.  The GNU tar maintainer has now chosen -j
     as the offical bzip2(1) compression option in GNU tar 1.13.18 and later.
     The -I option is for compatibility with Solaris's tar.

     bzip2(1), compress(1), gzip(1), pax(1), rmt(8)

     The tar format has a rich history, dating back to Sixth Edition UNIX.
     The current implementation of tar is the GNU implementation, which origi-
     nated as the public-domain tar written by John Gilmore.

     A cast of thousands, including [as listed in the ChangeLog file in the
     source] John Gilmore (author of original public domain version), Jay
     Fenlason (first GNU author), Joy Kendall, Jim Kingdon, David J.
     MacKenzie, Michael I Bushnell, Noah Friedman, and innumerable others who
     have contributed fixes and additions.

     Man page obtained by the FreeBSD group from the NetBSD 1.0 release.

     The -C feature does not work like historical tar programs, and is proba-
     bly untrustworthy.

     The -A command should work to join an arbitrary number of tar archives
     together, but it does not; attempting to do so leaves the end-of-archive
     blocks in place for the second and subsequent archives.

     The tar file format is a semi fixed width field format, and the field for
     device numbers were designed for 16 bit (8 major, 8 minor) and can not
     absorb our 32 bit (8 major, 16+8 minor) numbers.

FreeBSD 4.10                   December 23, 2000                  FreeBSD 4.10


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