tar

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tar is an archiver tool that provides the ability to create tar archives, as well as various other kinds of manipulation. The tar utility is often used for file storage, backup, and transportation.

By default, Gentoo provides GNU tar, app-arch/tar ('gtar'), which is installed via the @system set. However, Gentoo also provides bsdtar(1) , via the app-arch/libarchive package; once that package is installed, bsdtar can be used as the default tar provider by setting the libarchive USE flag on app-alternatives/tar .

For a list of formats supported by GNU tar, refer to the tar(5) man page; for a list of formats supported by bsdtar, refer to the libarchive-formats(5) man page. Both implementations support various compression formats; refer to the gtar(1) and bsdtar(1) man pages for details.

The information provided in the rest of this page assumes the use of GNU tar.

Installation

USE flags

USE flags for app-arch/tar Use this to make tarballs :)

acl Add support for Access Control Lists
minimal just install `tar`
nls Add Native Language Support (using gettext - GNU locale utilities)
selinux !!internal use only!! Security Enhanced Linux support, this must be set by the selinux profile or breakage will occur
test Enable dependencies and/or preparations necessary to run tests (usually controlled by FEATURES=test but can be toggled independently)
verify-sig Verify upstream signatures on distfiles
xattr Add support for extended attributes (filesystem-stored metadata)
Data provided by the Gentoo Package Database · Last update: 2026年08月13日 01:13 More information about USE flags

Emerge

After adjusting USE flags:

root #emerge --ask app-arch/tar

Configuration

It's possible to configure tar to use parallel versions of tools for compression, like app-arch/pigz .

FILE /etc/portage/env/app-arch/tar
# Use app-arch/lbzip2 for bzip2 and app-arch/pigz for gzip
EXTRA_ECONF="--with-bzip2=lbzip2 --with-gzip=pigz"

And install the relevant tools:

root #emerge --ask app-arch/lbzip2 app-arch/pigz

Then re-emerge tar:

root #emerge --oneshot app-arch/tar

Environment variables

user $tar --help

displays by default the short tar option summary, which is divided into sections. The exact visual representation of the help output is configurable via the ARGP_HELP_FMT environment variable. For more information please refer to GNU's tar manual

Usage

Invocation

help

user $tar --help
Usage: tar [OPTION...] [FILE]...
GNU 'tar' saves many files together into a single tape or disk archive, and can
restore individual files from the archive.
Examples:
 tar -cf archive.tar foo bar # Create archive.tar from files foo and bar.
 tar -tvf archive.tar # List all files in archive.tar verbosely.
 tar -xf archive.tar # Extract all files from archive.tar.
 Main operation mode:
 -A, --catenate, --concatenate append tar files to an archive
 -c, --create create a new archive
 --delete delete from the archive (not on mag tapes!)
 -d, --diff, --compare find differences between archive and file system
 -r, --append append files to the end of an archive
 --test-label test the archive volume label and exit
 -t, --list list the contents of an archive
 -u, --update only append files newer than copy in archive
 -x, --extract, --get extract files from an archive
 Operation modifiers:
 --check-device check device numbers when creating incremental
 archives (default)
 -g, --listed-incremental=FILE handle new GNU-format incremental backup
 -G, --incremental handle old GNU-format incremental backup
 --hole-detection=TYPE technique to detect holes
 --ignore-failed-read do not exit with nonzero on unreadable files
 --level=NUMBER dump level for created listed-incremental archive
 --no-check-device do not check device numbers when creating
 incremental archives
 --no-seek archive is not seekable
 -n, --seek archive is seekable
 --occurrence[=NUMBER] process only the NUMBERth occurrence of each file
 in the archive; this option is valid only in
 conjunction with one of the subcommands --delete,
 --diff, --extract or --list and when a list of
 files is given either on the command line or via
 the -T option; NUMBER defaults to 1
 --sparse-version=MAJOR[.MINOR]
 set version of the sparse format to use (implies
 --sparse)
 -S, --sparse handle sparse files efficiently
 Local file name selection:
 --add-file=FILE add given FILE to the archive (useful if its name
 starts with a dash)
 -C, --directory=DIR change to directory DIR
 --exclude=PATTERN exclude files, given as a PATTERN
 --exclude-backups exclude backup and lock files
 --exclude-caches exclude contents of directories containing
 CACHEDIR.TAG, except for the tag file itself
 --exclude-caches-all exclude directories containing CACHEDIR.TAG
 --exclude-caches-under exclude everything under directories containing
 CACHEDIR.TAG
 --exclude-ignore=FILE read exclude patterns for each directory from
 FILE, if it exists
 --exclude-ignore-recursive=FILE
 read exclude patterns for each directory and its
 subdirectories from FILE, if it exists
 --exclude-tag=FILE exclude contents of directories containing FILE,
 except for FILE itself
 --exclude-tag-all=FILE exclude directories containing FILE
 --exclude-tag-under=FILE exclude everything under directories
 containing FILE
 --exclude-vcs exclude version control system directories
 --exclude-vcs-ignores read exclude patterns from the VCS ignore files
 --no-null disable the effect of the previous --null option
 --no-recursion avoid descending automatically in directories
 --no-unquote do not unquote input file or member names
 --no-verbatim-files-from -T treats file names starting with dash as
 options (default)
 --null -T reads null-terminated names; implies
 --verbatim-files-from
 --recursion recurse into directories (default)
 -T, --files-from=FILE get names to extract or create from FILE
 --unquote unquote input file or member names (default)
 --verbatim-files-from -T reads file names verbatim (no escape or option
 handling)
 -X, --exclude-from=FILE exclude patterns listed in FILE
 File name matching options (affect both exclude and include patterns):
 --anchored patterns match file name start
 --ignore-case ignore case
 --no-anchored patterns match after any '/' (default for
 exclusion)
 --no-ignore-case case sensitive matching (default)
 --no-wildcards verbatim string matching
 --no-wildcards-match-slash wildcards do not match '/'
 --wildcards use wildcards (default for exclusion)
 --wildcards-match-slash wildcards match '/' (default for exclusion)
 Overwrite control:
 --keep-directory-symlink preserve existing symlinks to directories when
 extracting
 --keep-newer-files don't replace existing files that are newer than
 their archive copies
 -k, --keep-old-files don't replace existing files when extracting,
 treat them as errors
 --no-overwrite-dir preserve metadata of existing directories
 --one-top-level[=DIR] create a subdirectory to avoid having loose files
 extracted
 --overwrite overwrite existing files when extracting
 --overwrite-dir overwrite metadata of existing directories when
 extracting (default)
 --recursive-unlink empty hierarchies prior to extracting directory
 --remove-files remove files after adding them to the archive
 --skip-old-files don't replace existing files when extracting,
 silently skip over them
 -U, --unlink-first remove each file prior to extracting over it
 -W, --verify attempt to verify the archive after writing it
 Select output stream:
 --ignore-command-error ignore exit codes of children
 --no-ignore-command-error treat non-zero exit codes of children as
 error
 -O, --to-stdout extract files to standard output
 --to-command=COMMAND pipe extracted files to another program
 Handling of file attributes:
 --atime-preserve[=METHOD] preserve access times on dumped files, either
 by restoring the times after reading
 (METHOD='replace'; default) or by not setting the
 times in the first place (METHOD='system')
 --clamp-mtime only set time when the file is more recent than
 what was given with --mtime
 --delay-directory-restore delay setting modification times and
 permissions of extracted directories until the end
 of extraction
 --group=NAME force NAME as group for added files
 --group-map=FILE use FILE to map file owner GIDs and names
 --mode=CHANGES force (symbolic) mode CHANGES for added files
 --mtime=DATE-OR-FILE set mtime for added files from DATE-OR-FILE
 -m, --touch don't extract file modified time
 --no-delay-directory-restore
 cancel the effect of --delay-directory-restore
 option
 --no-same-owner extract files as yourself (default for ordinary
 users)
 --no-same-permissions apply the user's umask when extracting permissions
 from the archive (default for ordinary users)
 --numeric-owner always use numbers for user/group names
 --owner=NAME force NAME as owner for added files
 --owner-map=FILE use FILE to map file owner UIDs and names
 -p, --preserve-permissions, --same-permissions
 extract information about file permissions
 (default for superuser)
 --same-owner try extracting files with the same ownership as
 exists in the archive (default for superuser)
 --sort=ORDER directory sorting order: none (default), name or
 inode
 -s, --preserve-order, --same-order
 member arguments are listed in the same order as
 the files in the archive
 Handling of extended file attributes:
 --acls Enable the POSIX ACLs support
 --no-acls Disable the POSIX ACLs support
 --no-selinux Disable the SELinux context support
 --no-xattrs Disable extended attributes support
 --selinux Enable the SELinux context support
 --xattrs Enable extended attributes support
 --xattrs-exclude=MASK specify the exclude pattern for xattr keys
 --xattrs-include=MASK specify the include pattern for xattr keys
 Device selection and switching:
 --force-local archive file is local even if it has a colon
 -f, --file=ARCHIVE use archive file or device ARCHIVE
 -F, --info-script=NAME, --new-volume-script=NAME
 run script at end of each tape (implies -M)
 -L, --tape-length=NUMBER change tape after writing NUMBER x 1024 bytes
 -M, --multi-volume create/list/extract multi-volume archive
 --rmt-command=COMMAND use given rmt COMMAND instead of rmt
 --rsh-command=COMMAND use remote COMMAND instead of rsh
 --volno-file=FILE use/update the volume number in FILE
 Device blocking:
 -b, --blocking-factor=BLOCKS BLOCKS x 512 bytes per record
 -B, --read-full-records reblock as we read (for 4.2BSD pipes)
 -i, --ignore-zeros ignore zeroed blocks in archive (means EOF)
 --record-size=NUMBER NUMBER of bytes per record, multiple of 512
 Archive format selection:
 -H, --format=FORMAT create archive of the given format
 FORMAT is one of the following:
 gnu GNU tar 1.13.x format
 oldgnu GNU format as per tar <= 1.12
 pax POSIX 1003.1-2001 (pax) format
 posix same as pax
 ustar POSIX 1003.1-1988 (ustar) format
 v7 old V7 tar format
 --old-archive, --portability
 same as --format=v7
 --pax-option=keyword[[:]=value][,keyword[[:]=value]]...
 control pax keywords
 --posix same as --format=posix
 -V, --label=TEXT create archive with volume name TEXT; at
 list/extract time, use TEXT as a globbing pattern
 for volume name
 Compression options:
 -a, --auto-compress use archive suffix to determine the compression
 program
 -I, --use-compress-program=PROG
 filter through PROG (must accept -d)
 -j, --bzip2 filter the archive through bzip2
 -J, --xz filter the archive through xz
 --lzip filter the archive through lzip
 --lzma filter the archive through lzma
 --lzop filter the archive through lzop
 --no-auto-compress do not use archive suffix to determine the
 compression program
 --zstd filter the archive through zstd
 -z, --gzip, --gunzip, --ungzip filter the archive through gzip
 -Z, --compress, --uncompress filter the archive through compress
 Local file selection:
 --backup[=CONTROL] backup before removal, choose version CONTROL
 --hard-dereference follow hard links; archive and dump the files they
 refer to
 -h, --dereference follow symlinks; archive and dump the files they
 point to
 -K, --starting-file=MEMBER-NAME
 begin at member MEMBER-NAME when reading the
 archive
 --newer-mtime=DATE compare date and time when data changed only
 -N, --newer=DATE-OR-FILE, --after-date=DATE-OR-FILE
 only store files newer than DATE-OR-FILE
 --one-file-system stay in local file system when creating archive
 -P, --absolute-names don't strip leading '/'s from file names
 --suffix=STRING backup before removal, override usual suffix ('~'
 unless overridden by environment variable
 SIMPLE_BACKUP_SUFFIX)
 File name transformations:
 --strip-components=NUMBER strip NUMBER leading components from file
 names on extraction
 --transform=EXPRESSION, --xform=EXPRESSION
 use sed replace EXPRESSION to transform file
 names
 Informative output:
 --checkpoint[=NUMBER] display progress messages every NUMBERth record
 (default 10)
 --checkpoint-action=ACTION execute ACTION on each checkpoint
 --full-time print file time to its full resolution
 --index-file=FILE send verbose output to FILE
 -l, --check-links print a message if not all links are dumped
 --no-quote-chars=STRING disable quoting for characters from STRING
 --quote-chars=STRING additionally quote characters from STRING
 --quoting-style=STYLE set name quoting style; see below for valid STYLE
 values
 -R, --block-number show block number within archive with each message
 
 --show-defaults show tar defaults
 --show-omitted-dirs when listing or extracting, list each directory
 that does not match search criteria
 --show-snapshot-field-ranges
 show valid ranges for snapshot-file fields
 --show-transformed-names, --show-stored-names
 show file or archive names after transformation
 --totals[=SIGNAL] print total bytes after processing the archive;
 with an argument - print total bytes when this
 SIGNAL is delivered; Allowed signals are: SIGHUP,
 SIGQUIT, SIGINT, SIGUSR1 and SIGUSR2; the names
 without SIG prefix are also accepted
 --utc print file modification times in UTC
 -v, --verbose verbosely list files processed
 --warning=KEYWORD warning control
 -w, --interactive, --confirmation
 ask for confirmation for every action
 Compatibility options:
 -o when creating, same as --old-archive; when
 extracting, same as --no-same-owner
 Other options:
 -?, --help give this help list
 --restrict disable use of some potentially harmful options
 --usage give a short usage message
 --version print program version
Mandatory or optional arguments to long options are also mandatory or optional
for any corresponding short options.
The backup suffix is '~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX.
The version control may be set with --backup or VERSION_CONTROL, values are:
 none, off never make backups
 t, numbered make numbered backups
 nil, existing numbered if numbered backups exist, simple otherwise
 never, simple always make simple backups
Valid arguments for the --quoting-style option are:
 literal
 shell
 shell-always
 shell-escape
 shell-escape-always
 c
 c-maybe
 escape
 locale
 clocale
*This* tar defaults to:
--format=gnu -f- -b20 --quoting-style=escape --rmt-command=/usr/sbin/rmt

Most of the tar operations and options can be written in any of three forms: long, short, and old style.

Note
The "old style" option forms exist in GNU tar for compatibility with Unix tar.

Three most frequently used options

Creation
user $tar --create

or

user $tar -c
Listing
user $tar --list

or

user $tar -t
Extraction
user $tar --extract

or

user $tar -x

Some useful options are:

  • -xz: for tar.gz or .tgz.
  • -xy: for tar.bz2 or .tbz2.
  • -xJ: for tar.xz or .txz.


Note
The fastest way to extract a tarball is tar -xf tarball because it can recognize any additional extensions.
Additional options
  • To specify the name of an archive:
user $tar --file=archive-name

or

user $tar -f archive-name
  • For showing the files being worked on as tar is running:
user $tar --verbose

or

user $tar -v

Compression

There are many ways to create a compressed tar file, also known as a 'tarball'. The best one may be:

user $tar --auto-compress

or

user $tar -a

This option will select the compression program based on the suffix of the archive file name. For example:

user $tar caf archive.tar.bz2

This command will produce a bz2 tarball, while:

user $ tar -caf archive.tar.lzma

will produce an lzma tarball.

Note
As mentioned previously, the "old" style is maintained for compatibility reasons; therefore caf and -caf still work the same way.

Additional information

Due to tar's wide variety of options, it isn't possible to cover all the advanced features of this program within a single wiki entry. Some of the more advanced features include:

  • Adding files to existing archives;
  • Updating an archive;
  • Specifying options with --extract;
  • Backing up and restoring files;
  • Excluding some files; and
  • Crossing file system boundaries.

This information and more is available in the GNU tar manual

Removal

root #emerge --ask --depclean app-arch/tar

See also

  • Backup — prevent loss of data by ensuring it can be recovered.
  • Data compression — a list of some of the compression and file-archiver utilities available in Gentoo Linux

External resources