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

NAME
     tar -- manipulate tape archives

SYNOPSIS
     tar [bundled-flags	]	[	|  ...]
     tar {-c} [options]	[files | directories]
     tar {-r | -u} -f archive-file [options] [files | directories]
     tar {-t | -x} [options] [patterns]

DESCRIPTION
     tar creates and manipulates streaming archive files.  This	implementation
     can extract from tar, pax,	cpio, zip, jar,	ar, xar, rpm, 7-zip, and ISO
     9660 cdrom	images and can create tar, pax,	cpio, ar, zip, 7-zip, and shar
     archives.

     The first synopsis	form shows a "bundled" option word.  This usage	is
     provided for compatibility	with historical	implementations.  See COMPATI-
     BILITY below for details.

     The other synopsis	forms show the preferred usage.	 The first option to
     tar is a mode indicator from the following	list:
     -c	     Create a new archive containing the specified items.  The long
	     option form is --create.
     -r	     Like -c, but new entries are appended to the archive.  Note that
	     this only works on	uncompressed archives stored in	regular	files.
	     The -f option is required.	 The long option form is --append.
     -t	     List archive contents to stdout.  The long	option form is --list.
     -u	     Like -r, but new entries are added	only if	they have a modifica-
	     tion date newer than the corresponding entry in the archive.
	     Note that this only works on uncompressed archives	stored in reg-
	     ular files.  The -f option	is required.  The long form is
	     --update.
     -x	     Extract to	disk from the archive.	If a file with the same	name
	     appears more than once in the archive, each copy will be ex-
	     tracted, with later copies	overwriting (replacing)	earlier
	     copies.  The long option form is --extract.

     In	-c, -r,	or -u mode, each specified file	or directory is	added to the
     archive in	the order specified on the command line.  By default, the con-
     tents of each directory are also archived.

     In	extract	or list	mode, the entire command line is read and parsed be-
     fore the archive is opened.  The pathnames	or patterns on the command
     line indicate which items in the archive should be	processed.  Patterns
     are shell-style globbing patterns as documented in	tcsh(1).

OPTIONS
     Unless specifically stated	otherwise, options are applicable in all oper-
     ating modes.

     @archive
	     (c	and r modes only) The specified	archive	is opened and the en-
	     tries in it will be appended to the current archive.  As a	simple
	     example,
		   tar -c -f - newfile @original.tar
	     writes a new archive to standard output containing	a file newfile
	     and all of	the entries from original.tar.	In contrast,
		   tar -c -f - newfile original.tar
	     creates a new archive with	only two entries.  Similarly,
		   tar -czf - --format pax @-
	     reads an archive from standard input (whose format	will be	deter-
	     mined automatically) and converts it into a gzip-compressed pax-
	     format archive on stdout.	In this	way, tar can be	used to	con-
	     vert archives from	one format to another.

     -a, --auto-compress
	     (c	mode only) Use the archive suffix to decide a set of the for-
	     mat and the compressions.	As a simple example,
		   tar -a -cf archive.tgz source.c source.h
	     creates a new archive with	restricted pax format and gzip com-
	     pression,
		   tar -a -cf archive.tar.bz2.uu source.c source.h
	     creates a new archive with	restricted pax format and bzip2	com-
	     pression and uuencode compression,
		   tar -a -cf archive.zip source.c source.h
	     creates a new archive with	zip format,
		   tar -a -jcf archive.tgz source.c source.h
	     ignores the "-j" option, and creates a new	archive	with re-
	     stricted pax format and gzip compression,
		   tar -a -jcf archive.xxx source.c source.h
	     if	it is unknown suffix or	no suffix, creates a new archive with
	     restricted	pax format and bzip2 compression.

     --acls  (c, r, u, x modes only) Archive or	extract	POSIX.1e or NFSv4
	     ACLs.  This is the	reverse	of --no-acls and the default behavior
	     in	c, r, and u modes (except on Mac OS X) or if tar is run	in x
	     mode as root.  On Mac OS X	this option translates extended	ACLs
	     to	NFSv4 ACLs.  To	store extended ACLs the	--mac-metadata option
	     is	preferred.

     -B, --read-full-blocks
	     Ignored for compatibility with other tar(1) implementations.

     -b	blocksize, --block-size	blocksize
	     Specify the block size, in	512-byte records, for tape drive I/O.
	     As	a rule,	this argument is only needed when reading from or
	     writing to	tape drives, and usually not even then as the default
	     block size	of 20 records (10240 bytes) is very common.

     -C	directory, --cd	directory, --directory directory
	     In	c and r	mode, this changes the directory before	adding the
	     following files.  In x mode, change directories after opening the
	     archive but before	extracting entries from	the archive.

     --chroot
	     (x	mode only) chroot() to the current directory after processing
	     any -C options and	before extracting any files.

     --clear-nochange-fflags
	     (x	mode only) Before removing file	system objects to replace
	     them, clear platform-specific file	attributes or file flags that
	     might prevent removal.

     --exclude pattern
	     Do	not process files or directories that match the	specified pat-
	     tern.  Note that exclusions take precedence over patterns or
	     filenames specified on the	command	line.

     --exclude-vcs
	     Do	not process files or directories internally used by the	ver-
	     sion control systems `Arch', `Bazaar', `CVS', `Darcs',
	     `Mercurial', `RCS', `SCCS', `SVN' and `git'.

     --fflags
	     (c, r, u, x modes only) Archive or	extract	platform-specific file
	     attributes	or file	flags.	This is	the reverse of --no-fflags and
	     the default behavior in c,	r, and u modes or if tar is run	in x
	     mode as root.

     --format format
	     (c, r, u mode only) Use the specified format for the created ar-
	     chive.  Supported formats include "cpio", "pax", "shar", and
	     "ustar".  Other formats may also be supported; see
	     libarchive-formats(5) for more information	about currently-sup-
	     ported formats.  In r and u modes,	when extending an existing ar-
	     chive, the	format specified here must be compatible with the for-
	     mat of the	existing archive on disk.

     -f	file, --file file
	     Read the archive from or write the	archive	to the specified file.
	     The filename can be - for standard	input or standard output.  The
	     default varies by system; on FreeBSD, the default is /dev/sa0; on
	     Linux, the	default	is /dev/st0.

     --gid id
	     Use the provided group id number.	On extract, this overrides the
	     group id in the archive; the group	name in	the archive will be
	     ignored.  On create, this overrides the group id read from	disk;
	     if	--gname	is not also specified, the group name will be set to
	     match the group id.

     --gname name
	     Use the provided group name.  On extract, this overrides the
	     group name	in the archive;	if the provided	group name does	not
	     exist on the system, the group id (from the archive or from the
	     --gid option) will	be used	instead.  On create, this sets the
	     group name	that will be stored in the archive; the	name will not
	     be	verified against the system group database.

     -H	     (c	and r modes only) Symbolic links named on the command line
	     will be followed; the target of the link will be archived,	not
	     the link itself.

     -h	     (c	and r modes only) Synonym for -L.

     -I	     Synonym for -T.

     --help  Show usage.

     --hfsCompression
	     (x	mode only) Mac OS X specific (v10.6 or later). Compress	ex-
	     tracted regular files with	HFS+ compression.

     --ignore-zeros
	     An	alias of --options read_concatenated_archives for compatibil-
	     ity with GNU tar.

     --include pattern
	     Process only files	or directories that match the specified	pat-
	     tern.  Note that exclusions specified with	--exclude take prece-
	     dence over	inclusions.  If	no inclusions are explicitly speci-
	     fied, all entries are processed by	default.  The --include	option
	     is	especially useful when filtering archives.  For	example, the
	     command
		   tar -c -f new.tar --include='*foo*' @old.tgz
	     creates a new archive new.tar containing only the entries from
	     old.tgz containing	the string `foo'.

     -J, --xz
	     (c	mode only) Compress the	resulting archive with xz(1).  In ex-
	     tract or list modes, this option is ignored.  Note	that this tar
	     implementation recognizes XZ compression automatically when read-
	     ing archives.

     -j, --bzip, --bzip2, --bunzip2
	     (c	mode only) Compress the	resulting archive with bzip2(1).  In
	     extract or	list modes, this option	is ignored.  Note that this
	     tar implementation	recognizes bzip2 compression automatically
	     when reading archives.

     -k, --keep-old-files
	     (x	mode only) Do not overwrite existing files.  In	particular, if
	     a file appears more than once in an archive, later	copies will
	     not overwrite earlier copies.

     --keep-newer-files
	     (x	mode only) Do not overwrite existing files that	are newer than
	     the versions appearing in the archive being extracted.

     -L, --dereference
	     (c	and r modes only) All symbolic links will be followed.	Nor-
	     mally, symbolic links are archived	as such.  With this option,
	     the target	of the link will be archived instead.

     -l, --check-links
	     (c	and r modes only) Issue	a warning message unless all links to
	     each file are archived.

     --lrzip
	     (c	mode only) Compress the	resulting archive with lrzip(1).  In
	     extract or	list modes, this option	is ignored.  Note that this
	     tar implementation	recognizes lrzip compression automatically
	     when reading archives.

     --lz4   (c	mode only) Compress the	archive	with lz4-compatible compres-
	     sion before writing it.  In extract or list modes,	this option is
	     ignored.  Note that this tar implementation recognizes lz4	com-
	     pression automatically when reading archives.

     --zstd  (c	mode only) Compress the	archive	with zstd-compatible compres-
	     sion before writing it.  In extract or list modes,	this option is
	     ignored.  Note that this tar implementation recognizes zstd com-
	     pression automatically when reading archives.

     --lzma  (c	mode only) Compress the	resulting archive with the original
	     LZMA algorithm.  In extract or list modes,	this option is ig-
	     nored.  Use of this option	is discouraged and new archives	should
	     be	created	with --xz instead.  Note that this tar implementation
	     recognizes	LZMA compression automatically when reading archives.

     --lzop  (c	mode only) Compress the	resulting archive with lzop(1).	 In
	     extract or	list modes, this option	is ignored.  Note that this
	     tar implementation	recognizes LZO compression automatically when
	     reading archives.

     -m, --modification-time
	     (x	mode only) Do not extract modification time.  By default, the
	     modification time is set to the time stored in the	archive.

     --mac-metadata
	     (c, r, u and x mode only) Mac OS X	specific.  Archive or extract
	     extended ACLs and extended	file attributes	using copyfile(3) in
	     AppleDouble format.  This is the reverse of --no-mac-metadata.
	     and the default behavior in c, r, and u modes or if tar is	run in
	     x mode as root.

     -n, --norecurse, --no-recursion
	     Do	not operate recursively	on the content of directories.

     --newer date
	     (c, r, u modes only) Only include files and directories newer
	     than the specified	date.  This compares ctime entries.

     --newer-mtime date
	     (c, r, u modes only) Like --newer,	except it compares mtime en-
	     tries instead of ctime entries.

     --newer-than file
	     (c, r, u modes only) Only include files and directories newer
	     than the specified	file.  This compares ctime entries.

     --newer-mtime-than	file
	     (c, r, u modes only) Like --newer-than, except it compares	mtime
	     entries instead of	ctime entries.

     --nodump
	     (c	and r modes only) Honor	the nodump file	flag by	skipping this
	     file.

     --nopreserveHFSCompression
	     (x	mode only) Mac OS X specific (v10.6 or later). Do not compress
	     extracted regular files which were	compressed with	HFS+ compres-
	     sion before archived.  By default,	compress the regular files
	     again with	HFS+ compression.

     --null  (use with -I or -T) Filenames or patterns are separated by	null
	     characters, not by	newlines.  This	is often used to read file-
	     names output by the -print0 option	to find(1).

     --no-acls
	     (c, r, u, x modes only) Do	not archive or extract POSIX.1e	or
	     NFSv4 ACLs.  This is the reverse of --acls	and the	default	behav-
	     ior if tar	is run as non-root in x	mode (on Mac OS	X as any user
	     in	c, r, u	and x modes).

     --no-fflags
	     (c, r, u, x modes only) Do	not archive or extract file attributes
	     or	file flags.  This is the reverse of --fflags and the default
	     behavior if tar is	run as non-root	in x mode.

     --no-mac-metadata
	     (x	mode only) Mac OS X specific.  Do not archive or extract ACLs
	     and extended file attributes using	copyfile(3) in AppleDouble
	     format.  This is the reverse of --mac-metadata.  and the default
	     behavior if tar is	run as non-root	in x mode.

     --no-read-sparse
	     (c, r, u modes only) Do not read sparse file information from
	     disk.  This is the	reverse	of --read-sparse.

     --no-safe-writes
	     (x	mode only) Do not create temporary files and use rename(2) to
	     replace the original ones.	 This is the reverse of	--safe-writes.

     --no-same-owner
	     (x	mode only) Do not extract owner	and group IDs.	This is	the
	     reverse of	--same-owner and the default behavior if tar is	run as
	     non-root.

     --no-same-permissions
	     (x	mode only) Do not extract full permissions (SGID, SUID,	sticky
	     bit, file attributes or file flags, extended file attributes and
	     ACLs).  This is the reverse of -p and the default behavior	if tar
	     is	run as non-root.

     --no-xattrs
	     (c, r, u, x modes only) Do	not archive or extract extended	file
	     attributes.  This is the reverse of --xattrs and the default be-
	     havior if tar is run as non-root in x mode.

     --numeric-owner
	     This is equivalent	to --uname "" --gname "".  On extract, it
	     causes user and group names in the	archive	to be ignored in favor
	     of	the numeric user and group ids.	 On create, it causes user and
	     group names to not	be stored in the archive.

     -O, --to-stdout
	     (x, t modes only) In extract (-x) mode, files will	be written to
	     standard out rather than being extracted to disk.	In list	(-t)
	     mode, the file listing will be written to stderr rather than the
	     usual stdout.

     -o	     (x	mode) Use the user and group of	the user running the program
	     rather than those specified in the	archive.  Note that this has
	     no	significance unless -p is specified, and the program is	being
	     run by the	root user.  In this case, the file modes and flags
	     from the archive will be restored,	but ACLs or owner information
	     in	the archive will be discarded.

     -o	     (c, r, u mode) A synonym for --format ustar

     --older date
	     (c, r, u modes only) Only include files and directories older
	     than the specified	date.  This compares ctime entries.

     --older-mtime date
	     (c, r, u modes only) Like --older,	except it compares mtime en-
	     tries instead of ctime entries.

     --older-than file
	     (c, r, u modes only) Only include files and directories older
	     than the specified	file.  This compares ctime entries.

     --older-mtime-than	file
	     (c, r, u modes only) Like --older-than, except it compares	mtime
	     entries instead of	ctime entries.

     --one-file-system
	     (c, r, and	u modes) Do not	cross mount points.

     --options options
	     Select optional behaviors for particular modules.	The argument
	     is	a text string containing comma-separated keywords and values.
	     These are passed to the modules that handle particular formats to
	     control how those formats will behave.  Each option has one of
	     the following forms:
	     key=value
		     The key will be set to the	specified value	in every mod-
		     ule that supports it.  Modules that do not	support	this
		     key will ignore it.
	     key     The key will be enabled in	every module that supports it.
		     This is equivalent	to key=1.
	     !key    The key will be disabled in every module that supports
		     it.
	     module:key=value, module:key, module:!key
		     As	above, but the corresponding key and value will	be
		     provided only to modules whose name matches module.

	     The complete list of supported modules and	keys for create	and
	     append modes is in	archive_write_set_options(3) and for extract
	     and list modes in archive_read_set_options(3).

	     Examples of supported options:
	     iso9660:joliet
		     Support Joliet extensions.	 This is enabled by default,
		     use !joliet or iso9660:!joliet to disable.
	     iso9660:rockridge
		     Support Rock Ridge	extensions.  This is enabled by	de-
		     fault, use	!rockridge or iso9660:!rockridge to disable.
	     gzip:compression-level
		     A decimal integer from 1 to 9 specifying the gzip com-
		     pression level.
	     gzip:timestamp
		     Store timestamp.  This is enabled by default, use
		     !timestamp	or gzip:!timestamp to disable.
	     lrzip:compression=type
		     Use type as compression method.  Supported	values are
		     bzip2, gzip, lzo (ultra fast), and	zpaq (best, extremely
		     slow).
	     lrzip:compression-level
		     A decimal integer from 1 to 9 specifying the lrzip	com-
		     pression level.
	     lz4:compression-level
		     A decimal integer from 1 to 9 specifying the lzop com-
		     pression level.
	     lz4:stream-checksum
		     Enable stream checksum.  This is by default, use
		     lz4:!stream-checksum to disable.
	     lz4:block-checksum
		     Enable block checksum (Disabled by	default).
	     lz4:block-size
		     A decimal integer from 4 to 7 specifying the lz4 compres-
		     sion block	size (7	is set by default).
	     lz4:block-dependence
		     Use the previous block of the block being compressed for
		     a compression dictionary to improve compression ratio.
	     zstd:compression-level
		     A decimal integer specifying the zstd compression level.
		     Supported values depend on	the library version, common
		     values are	from 1 to 22.
	     zstd:threads
		     Specify the number	of worker threads to use.  Setting
		     threads to	a special value	0 makes	zstd(1)	use as many
		     threads as	there are CPU cores on the system.
	     lzop:compression-level
		     A decimal integer from 1 to 9 specifying the lzop com-
		     pression level.
	     xz:compression-level
		     A decimal integer from 0 to 9 specifying the xz compres-
		     sion level.
	     xz:threads
		     Specify the number	of worker threads to use.  Setting
		     threads to	a special value	0 makes	xz(1) use as many
		     threads as	there are CPU cores on the system.
	     mtree:keyword
		     The mtree writer module allows you	to specify which mtree
		     keywords will be included in the output.  Supported key-
		     words include: cksum, device, flags, gid, gname, indent,
		     link, md5,	mode, nlink, rmd160, sha1, sha256, sha384,
		     sha512, size, time, uid, uname.  The default is equiva-
		     lent to: "device, flags, gid, gname, link,	mode, nlink,
		     size, time, type, uid, uname".
	     mtree:all
		     Enables all of the	above keywords.	 You can also use
		     mtree:!all	to disable all keywords.
	     mtree:use-set
		     Enable generation of /set lines in	the output.
	     mtree:indent
		     Produce human-readable output by indenting	options	and
		     splitting lines to	fit into 80 columns.
	     zip:compression=type
		     Use type as compression method.  Supported	values are
		     store (uncompressed) and deflate (gzip algorithm).
	     zip:encryption
		     Enable encryption using traditional zip encryption.
	     zip:encryption=type
		     Use type as encryption type.  Supported values are
		     zipcrypt (traditional zip encryption), aes128 (WinZip
		     AES-128 encryption) and aes256 (WinZip AES-256 encryp-
		     tion).
	     read_concatenated_archives
		     Ignore zeroed blocks in the archive, which	occurs when
		     multiple tar archives have	been concatenated together.
		     Without this option, only the contents of the first con-
		     catenated archive would be	read.  This option is compara-
		     ble to the	-i, --ignore-zeros option of GNU tar.
	     If	a provided option is not supported by any module, that is a
	     fatal error.

     -P, --absolute-paths
	     Preserve pathnames.  By default, absolute pathnames (those	that
	     begin with	a / character) have the	leading	slash removed both
	     when creating archives and	extracting from	them.  Also, tar will
	     refuse to extract archive entries whose pathnames contain .. or
	     whose target directory would be altered by	a symlink.  This op-
	     tion suppresses these behaviors.

     -p, --insecure, --preserve-permissions
	     (x	mode only) Preserve file permissions.  Attempt to restore the
	     full permissions, including file modes, file attributes or	file
	     flags, extended file attributes and ACLs, if available, for each
	     item extracted from the archive.  This is the reverse of
	     --no-same-permissions and the default if tar is being run as
	     root.  It can be partially	overridden by also specifying
	     --no-acls,	--no-fflags, --no-mac-metadata or --no-xattrs.

     --passphrase passphrase
	     The passphrase is used to extract or create an encrypted archive.
	     Currently,	zip is the only	supported format that supports encryp-
	     tion.  You	shouldn't use this option unless you realize how inse-
	     cure use of this option is.

     --posix
	     (c, r, u mode only) Synonym for --format pax

     -q, --fast-read
	     (x	and t mode only) Extract or list only the first	archive	entry
	     that matches each pattern or filename operand.  Exit as soon as
	     each specified pattern or filename	has been matched.  By default,
	     the archive is always read	to the very end, since there can be
	     multiple entries with the same name and, by convention, later en-
	     tries overwrite earlier entries.  This option is provided as a
	     performance optimization.

     --read-sparse
	     (c, r, u modes only) Read sparse file information from disk.
	     This is the reverse of --no-read-sparse and the default behavior.

     -S	     (x	mode only) Extract files as sparse files.  For every block on
	     disk, check first if it contains only NULL	bytes and seek over it
	     otherwise.	 This works similar to the conv=sparse option of dd.

     -s	pattern
	     Modify file or archive member names according to pattern.	The
	     pattern has the format /old/new/[ghHprRsS]	where old is a basic
	     regular expression, new is	the replacement	string of the matched
	     part, and the optional trailing letters modify how	the replace-
	     ment is handled.  If old is not matched, the pattern is skipped.
	     Within new, ~ is substituted with the match, \1 to	\9 with	the
	     content of	the corresponding captured group.  The optional	trail-
	     ing g specifies that matching should continue after the matched
	     part and stop on the first	unmatched pattern.  The	optional
	     trailing s	specifies that the pattern applies to the value	of
	     symbolic links.  The optional trailing p specifies	that after a
	     successful	substitution the original path name and	the new	path
	     name should be printed to standard	error.	Optional trailing H,
	     R,	or S characters	suppress substitutions for hardlink targets,
	     regular filenames,	or symlink targets, respectively.  Optional
	     trailing h, r, or s characters enable substitutions for hardlink
	     targets, regular filenames, or symlink targets, respectively.
	     The default is hrs	which applies substitutions to all names.  In
	     particular, it is never necessary to specify h, r,	or s.

     --safe-writes
	     (x	mode only) Extract files atomically.  By default tar unlinks
	     the original file with the	same name as the extracted file	(if it
	     exists), and then creates it immediately under the	same name and
	     writes to it.  For	a short	period of time,	applications trying to
	     access the	file might not find it,	or see incomplete results.  If
	     --safe-writes is enabled, tar first creates a unique temporary
	     file, then	writes the new contents	to the temporary file, and fi-
	     nally renames the temporary file to its final name	atomically us-
	     ing rename(2).  This guarantees that an application accessing the
	     file, will	either see the old contents or the new contents	at all
	     times.

     --same-owner
	     (x	mode only) Extract owner and group IDs.	 This is the reverse
	     of	--no-same-owner	and the	default	behavior if tar	is run as
	     root.

     --strip-components	count
	     Remove the	specified number of leading path elements.  Pathnames
	     with fewer	elements will be silently skipped.  Note that the
	     pathname is edited	after checking inclusion/exclusion patterns
	     but before	security checks.

     -T	filename, --files-from filename
	     In	x or t mode, tar will read the list of names to	be extracted
	     from filename.  In	c mode,	tar will read names to be archived
	     from filename.  The special name "-C" on a	line by	itself will
	     cause the current directory to be changed to the directory	speci-
	     fied on the following line.  Names	are terminated by newlines un-
	     less --null is specified.	Note that --null also disables the
	     special handling of lines containing "-C".	 Note:	If you are
	     generating	lists of files using find(1), you probably want	to use
	     -n	as well.

     --totals
	     (c, r, u modes only) After	archiving all files, print a summary
	     to	stderr.

     -U, --unlink, --unlink-first
	     (x	mode only) Unlink files	before creating	them.  This can	be a
	     minor performance optimization if most files already exist, but
	     can make things slower if most files do not already exist.	 This
	     flag also causes tar to remove intervening	directory symlinks in-
	     stead of reporting	an error.  See the SECURITY section below for
	     more details.

     --uid id
	     Use the provided user id number and ignore	the user name from the
	     archive.  On create, if --uname is	not also specified, the	user
	     name will be set to match the user	id.

     --uname name
	     Use the provided user name.  On extract, this overrides the user
	     name in the archive; if the provided user name does not exist on
	     the system, it will be ignored and	the user id (from the archive
	     or	from the --uid option) will be used instead.  On create, this
	     sets the user name	that will be stored in the archive; the	name
	     is	not verified against the system	user database.

     --use-compress-program program
	     Pipe the input (in	x or t mode) or	the output (in c mode) through
	     program instead of	using the builtin compression support.

     -v, --verbose
	     Produce verbose output.  In create	and extract modes, tar will
	     list each file name as it is read from or written to the archive.
	     In	list mode, tar will produce output similar to that of ls(1).
	     An	additional -v option will also provide ls-like details in cre-
	     ate and extract mode.

     --version
	     Print version of tar and libarchive, and exit.

     -w, --confirmation, --interactive
	     Ask for confirmation for every action.

     -X	filename, --exclude-from filename
	     Read a list of exclusion patterns from the	specified file.	 See
	     --exclude for more	information about the handling of exclusions.

     --xattrs
	     (c, r, u, x modes only) Archive or	extract	extended file at-
	     tributes.	This is	the reverse of --no-xattrs and the default be-
	     havior in c, r, and u modes or if tar is run in x mode as root.

     -y	     (c	mode only) Compress the	resulting archive with bzip2(1).  In
	     extract or	list modes, this option	is ignored.  Note that this
	     tar implementation	recognizes bzip2 compression automatically
	     when reading archives.

     -Z, --compress, --uncompress
	     (c	mode only) Compress the	resulting archive with compress(1).
	     In	extract	or list	modes, this option is ignored.	Note that this
	     tar implementation	recognizes compress compression	automatically
	     when reading archives.

     -z, --gunzip, --gzip
	     (c	mode only) Compress the	resulting archive with gzip(1).	 In
	     extract or	list modes, this option	is ignored.  Note that this
	     tar implementation	recognizes gzip	compression automatically when
	     reading archives.

ENVIRONMENT
     The following environment variables affect	the execution of tar:

     TAR_READER_OPTIONS
		The default options for	format readers and compression read-
		ers.  The --options option overrides this.

     TAR_WRITER_OPTIONS
		The default options for	format writers and compression writ-
		ers.  The --options option overrides this.

     LANG	The locale to use.  See	environ(7) for more information.

     TAPE	The default device.  The -f option overrides this.  Please see
		the description	of the -f option above for more	details.

     TZ		The timezone to	use when displaying dates.  See	environ(7) for
		more information.

EXIT STATUS
     The tar utility exits 0 on	success, and >0	if an error occurs.

EXAMPLES
     The following creates a new archive called	file.tar.gz that contains two
     files source.c and	source.h:
	   tar -czf file.tar.gz	source.c source.h

     To	view a detailed	table of contents for this archive:
	   tar -tvf file.tar.gz

     To	extract	all entries from the archive on	the default tape drive:
	   tar -x

     To	examine	the contents of	an ISO 9660 cdrom image:
	   tar -tf image.iso

     To	move file hierarchies, invoke tar as
	   tar -cf - -C	srcdir . | tar -xpf - -C destdir
     or	more traditionally
	   cd srcdir ; tar -cf - . | (cd destdir ; tar -xpf -)

     In	create mode, the list of files and directories to be archived can also
     include directory change instructions of the form -Cfoo/baz and archive
     inclusions	of the form @archive-file.  For	example, the command line
	   tar -c -f new.tar foo1 @old.tgz -C/tmp foo2
     will create a new archive new.tar.	 tar will read the file	foo1 from the
     current directory and add it to the output	archive.  It will then read
     each entry	from old.tgz and add those entries to the output archive.  Fi-
     nally, it will switch to the /tmp directory and add foo2 to the output
     archive.

     An	input file in mtree(5) format can be used to create an output archive
     with arbitrary ownership, permissions, or names that differ from existing
     data on disk:

	   $ cat input.mtree
	   #mtree
	   usr/bin uid=0 gid=0 mode=0755 type=dir
	   usr/bin/ls uid=0 gid=0 mode=0755 type=file content=myls
	   $ tar -cvf output.tar @input.mtree

     The --newer and --newer-mtime switches accept a variety of	common date
     and time specifications, including	"12 Mar	2005 7:14:29pm", "2005-03-12
     19:14", "5	minutes	ago", and "19:14 PST May 1".

     The --options argument can	be used	to control various details of archive
     generation	or reading.  For example, you can generate mtree output	which
     only contains type, time, and uid keywords:
	   tar -cf file.tar --format=mtree --options='!all,type,time,uid' dir
     or	you can	set the	compression level used by gzip or xz compression:
	   tar -czf file.tar --options='compression-level=9'.
     For more details, see the explanation of the archive_read_set_options()
     and archive_write_set_options() API calls that are	described in
     archive_read(3) and archive_write(3).

COMPATIBILITY
     The bundled-arguments format is supported for compatibility with historic
     implementations.  It consists of an initial word (with no leading - char-
     acter) in which each character indicates an option.  Arguments follow as
     separate words.  The order	of the arguments must match the	order of the
     corresponding characters in the bundled command word.  For	example,
	   tar tbf 32 file.tar
     specifies three flags t, b, and f.	 The b and f flags both	require	argu-
     ments, so there must be two additional items on the command line.	The 32
     is	the argument to	the b flag, and	file.tar is the	argument to the	f
     flag.

     The mode options c, r, t, u, and x	and the	options	b, f, l, m, o, v, and
     w comply with SUSv2.

     For maximum portability, scripts that invoke tar should use the bundled-
     argument format above, should limit themselves to the c, t, and x modes,
     and the b,	f, m, v, and w options.

     Additional	long options are provided to improve compatibility with	other
     tar implementations.

SECURITY
     Certain security issues are common	to many	archiving programs, including
     tar.  In particular, carefully-crafted archives can request that tar ex-
     tract files to locations outside of the target directory.	This can po-
     tentially be used to cause	unwitting users	to overwrite files they	did
     not intend	to overwrite.  If the archive is being extracted by the	supe-
     ruser, any	file on	the system can potentially be overwritten.  There are
     three ways	this can happen.  Although tar has mechanisms to protect
     against each one, savvy users should be aware of the implications:

     +o	     Archive entries can have absolute pathnames.  By default, tar re-
	     moves the leading / character from	filenames before restoring
	     them to guard against this	problem.

     +o	     Archive entries can have pathnames	that include ..	components.
	     By	default, tar will not extract files containing .. components
	     in	their pathname.

     +o	     Archive entries can exploit symbolic links	to restore files to
	     other directories.	 An archive can	restore	a symbolic link	to an-
	     other directory, then use that link to restore a file into	that
	     directory.	 To guard against this,	tar checks each	extracted path
	     for symlinks.  If the final path element is a symlink, it will be
	     removed and replaced with the archive entry.  If -U is specified,
	     any intermediate symlink will also	be unconditionally removed.
	     If	neither	-U nor -P is specified,	tar will refuse	to extract the
	     entry.
     To	protect	yourself, you should be	wary of	any archives that come from
     untrusted sources.	 You should examine the	contents of an archive with
	   tar -tf filename
     before extraction.	 You should use	the -k option to ensure	that tar will
     not overwrite any existing	files or the -U	option to remove any pre-ex-
     isting files.  You	should generally not extract archives while running
     with super-user privileges.  Note that the	-P option to tar disables the
     security checks above and allows you to extract an	archive	while preserv-
     ing any absolute pathnames, .. components,	or symlinks to other directo-
     ries.

SEE ALSO
     bzip2(1), compress(1), cpio(1), gzip(1), mt(1), pax(1), shar(1), xz(1),
     libarchive(3), libarchive-formats(5), tar(5)

STANDARDS
     There is no current POSIX standard	for the	tar command; it	appeared in
     ISO/IEC 9945-1:1996 ("POSIX.1") but was dropped from IEEE Std 1003.1-2001
     ("POSIX.1").  The options supported by this implementation	were developed
     by	surveying a number of existing tar implementations as well as the old
     POSIX specification for tar and the current POSIX specification for pax.

     The ustar and pax interchange file	formats	are defined by IEEE Std
     1003.1-2001 ("POSIX.1") for the pax command.

HISTORY
     A tar command appeared in Seventh Edition Unix, which was released	in
     January, 1979.  There have	been numerous other implementations, many of
     which extended the	file format.  John Gilmore's pdtar public-domain im-
     plementation (circa November, 1987) was quite influential,	and formed the
     basis of GNU tar.	GNU tar	was included as	the standard system tar	in
     FreeBSD beginning with FreeBSD 1.0.

     This is a complete	re-implementation based	on the libarchive(3) library.
     It	was first released with	FreeBSD	5.4 in May, 2005.

BUGS
     This program follows ISO/IEC 9945-1:1996 ("POSIX.1") for the definition
     of	the -l option.	Note that GNU tar prior	to version 1.15	treated	-l as
     a synonym for the --one-file-system option.

     The -C dir	option may differ from historic	implementations.

     All archive output	is written in correctly-sized blocks, even if the out-
     put is being compressed.  Whether or not the last output block is padded
     to	a full block size varies depending on the format and the output	de-
     vice.  For	tar and	cpio formats, the last block of	output is padded to a
     full block	size if	the output is being written to standard	output or to a
     character or block	device such as a tape drive.  If the output is being
     written to	a regular file,	the last block will not	be padded.  Many com-
     pressors, including gzip(1) and bzip2(1), complain	about the null padding
     when decompressing	an archive created by tar, although they still extract
     it	correctly.

     The compression and decompression is implemented internally, so there may
     be	insignificant differences between the compressed output	generated by
	   tar -czf - file
     and that generated	by
	   tar -cf - file | gzip

     The default should	be to read and write archives to the standard I/O
     paths, but	tradition (and POSIX) dictates otherwise.

     The r and u modes require that the	archive	be uncompressed	and located in
     a regular file on disk.  Other archives can be modified using c mode with
     the @archive-file extension.

     To	archive	a file called @foo or -foo you must specify it as ./@foo or
     ./-foo, respectively.

     In	create mode, a leading ./ is always removed.  A	leading	/ is stripped
     unless the	-P option is specified.

     There needs to be better support for file selection on both create	and
     extract.

     There is not yet any support for multi-volume archives.

     Converting	between	dissimilar archive formats (such as tar	and cpio) us-
     ing the @-	convention can cause hard link information to be lost.	(This
     is	a consequence of the incompatible ways that different archive formats
     store hardlink information.)