TAR

Section: GNU TAR Manual (1)
Updated: July 13, 2020
Page Index
 

NAME

tar - an archiving utility  

SYNOPSIS

 

Traditional usage

tar {A|c|d|r|t|u|x}[GnSkUWOmpsMBiajJzZhPlRvwo] [ARG...]  

UNIX-style usage

tar -A [OPTIONS] ARCHIVE ARCHIVE

tar -c [-f ARCHIVE] [OPTIONS] [FILE...]

tar -d [-f ARCHIVE] [OPTIONS] [FILE...]

tar -t [-f ARCHIVE] [OPTIONS] [MEMBER...]

tar -r [-f ARCHIVE] [OPTIONS] [FILE...]

tar -u [-f ARCHIVE] [OPTIONS] [FILE...]

tar -x [-f ARCHIVE] [OPTIONS] [MEMBER...]  

GNU-style usage

tar {--catenate|--concatenate} [OPTIONS] ARCHIVE ARCHIVE

tar --create [--file ARCHIVE] [OPTIONS] [FILE...]

tar {--diff|--compare} [--file ARCHIVE] [OPTIONS] [FILE...]

tar --delete [--file ARCHIVE] [OPTIONS] [MEMBER...]

tar --append [-f ARCHIVE] [OPTIONS] [FILE...]

tar --list [-f ARCHIVE] [OPTIONS] [MEMBER...]

tar --test-label [--file ARCHIVE] [OPTIONS] [LABEL...]

tar --update [--file ARCHIVE] [OPTIONS] [FILE...]

tar --update [-f ARCHIVE] [OPTIONS] [FILE...]

tar {--extract|--get} [-f ARCHIVE] [OPTIONS] [MEMBER...]  

NOTE

This manpage is a short description of GNU tar. For a detailed discussion, including examples and usage recommendations, refer to the GNU Tar Manual available in texinfo format. If the info reader and the tar documentation are properly installed on your system, the command

info tar

should give you access to the complete manual.

You can also view the manual using the info mode in emacs(1), or find it in various formats online at

http://www.gnu.org/software/tar/manual

If any discrepancies occur between this manpage and the GNU Tar Manual, the later shall be considered the authoritative source.  

DESCRIPTION

GNU tar is an archiving program designed to store multiple files in a single file (an archive), and to manipulate such archives. The archive can be either a regular file or a device (e.g. a tape drive, hence the name of the program, which stands for tape archiver), which can be located either on the local or on a remote machine.

 

Option styles

Options to GNU tar can be given in three different styles. In traditional style, the first argument is a cluster of option letters and all subsequent arguments supply arguments to those options that require them. The arguments are read in the same order as the option letters. Any command line words that remain after all options has been processed are treated as non-optional arguments: file or archive member names.

For example, the c option requires creating the archive, the v option requests the verbose operation, and the f option takes an argument that sets the name of the archive to operate upon. The following command, written in the traditional style, instructs tar to store all files from the directory /etc into the archive file etc.tar verbosely listing the files being archived:

tar cfv etc.tar /etc

In UNIX or short-option style, each option letter is prefixed with a single dash, as in other command line utilities. If an option takes argument, the argument follows it, either as a separate command line word, or immediately following the option. However, if the option takes an optional argument, the argument must follow the option letter without any intervening whitespace, as in -g/tmp/snar.db.

Any number of options not taking arguments can be clustered together after a single dash, e.g. -vkp. Options that take arguments (whether mandatory or optional), can appear at the end of such a cluster, e.g. -vkpf a.tar.

The example command above written in the short-option style could look like:

tar -cvf etc.tar /etc or tar -c -v -f etc.tar /etc

In GNU or long-option style, each option begins with two dashes and has a meaningful name, consisting of lower-case letters and dashes. When used, the long option can be abbreviated to its initial letters, provided that this does not create ambiguity. Arguments to long options are supplied either as a separate command line word, immediately following the option, or separated from the option by an equals sign with no intervening whitespace. Optional arguments must always use the latter method.

Here are several ways of writing the example command in this style:

tar --create --file etc.tar --verbose /etc or (abbreviating some options): tar --cre --file=etc.tar --verb /etc

The options in all three styles can be intermixed, although doing so with old options is not encouraged.  

Operation mode

The options listed in the table below tell GNU tar what operation it is to perform. Exactly one of them must be given. Meaning of non-optional arguments depends on the operation mode requested.
-A, --catenate, --concatenate
Append archive to the end of another archive. The arguments are treated as the names of archives to append. All archives must be of the same format as the archive they are appended to, otherwise the resulting archive might be unusable with non-GNU implementations of tar. Notice also that when more than one archive is given, the members from archives other than the first one will be accessible in the resulting archive only if using the -i (--ignore-zeros) option.

Compressed archives cannot be concatenated.

-c, --create
Create a new archive. Arguments supply the names of the files to be archived. Directories are archived recursively, unless the --no-recursion option is given.
-d, --diff, --compare
Find differences between archive and file system. The arguments are optional and specify archive members to compare. If not given, the current working directory is assumed.
--delete
Delete from the archive. The arguments supply names of the archive members to be removed. At least one argument must be given.

This option does not operate on compressed archives. There is no short option equivalent.

-r, --append
Append files to the end of an archive. Arguments have the same meaning as for -c (--create).
-t, --list
List the contents of an archive. Arguments are optional. When given, they specify the names of the members to list.
--test-label
Test the archive volume label and exit. When used without arguments, it prints the volume label (if any) and exits with status 0. When one or more command line arguments are given. tar compares the volume label with each argument. It exits with code 0 if a match is found, and with code 1 otherwise. No output is displayed, unless used together with the -v (--verbose) option.

There is no short option equivalent for this option.

-u, --update
Append files which are newer than the corresponding copy in the archive. Arguments have the same meaning as with -c and -r options. Notice, that newer files don't replace their old archive copies, but instead are appended to the end of archive. The resulting archive can thus contain several members of the same name, corresponding to various versions of the same file.
-x, --extract, --get
Extract files from an archive. Arguments are optional. When given, they specify names of the archive members to be extracted.
--show-defaults
Show built-in defaults for various tar options and exit. No arguments are allowed.
-?, --help
Display a short option summary and exit. No arguments allowed.
--usage
Display a list of available options and exit. No arguments allowed.
--version
Print program version and copyright information and exit.
 

OPTIONS

 

Operation modifiers

--check-device
Check device numbers when creating incremental archives (default).
-g, --listed-incremental=FILE
Handle new GNU-format incremental backups. FILE is the name of a snapshot file, where tar stores additional information which is used to decide which files changed since the previous incremental dump and, consequently, must be dumped again. If FILE does not exist when creating an archive, it will be created and all files will be added to the resulting archive (the level 0 dump). To create incremental archives of non-zero level N, create a copy of the snapshot file created during the level N-1, and use it as FILE.

When listing or extracting, the actual contents of FILE is not inspected, it is needed only due to syntactical requirements. It is therefore common practice to use /dev/null in its place.

--hole-detection=METHOD
Use METHOD to detect holes in sparse files. This option implies --sparse. Valid values for METHOD are seek and raw. Default is seek with fallback to raw when not applicable.
-G, --incremental
Handle old GNU-format incremental backups.
--ignore-failed-read
Do not exit with nonzero on unreadable files.
--level=NUMBER
Set dump level for created listed-incremental archive. Currently only --level=0 is meaningful: it instructs tar to truncate the snapshot file before dumping, thereby forcing a level 0 dump.
-n, --seek
Assume the archive is seekable. Normally tar determines automatically whether the archive can be seeked or not. This option is intended for use in cases when such recognition fails. It takes effect only if the archive is open for reading (e.g. with --list or --extract options).
--no-check-device
Do not check device numbers when creating incremental archives.
--no-seek
Assume the archive is not seekable.
--occurrence[=N]
Process only the Nth occurrence of each file in the archive. This option is valid only when used with one of the following subcommands: --delete, --diff, --extract or --list and when a list of files is given either on the command line or via the -T option. The default N is 1.
--restrict
Disable the use of some potentially harmful options.
--sparse-version=MAJOR[.MINOR]
Set version of the sparse format to use (implies --sparse). This option implies --sparse. Valid argument values are 0.0, 0.1, and 1.0. For a detailed discussion of sparse formats, refer to the GNU Tar Manual, appendix D, "Sparse Formats". Using info reader, it can be accessed running the following command: info tar 'Sparse Formats'.
-S, --sparse
Handle sparse files efficiently. Some files in the file system may have segments which were actually never written (quite often these are database files created by such systems as DBM). When given this option, tar attempts to determine if the file is sparse prior to archiving it, and if so, to reduce the resulting archive size by not dumping empty parts of the file.
 

Overwrite control

These options control tar actions when extracting a file over an existing copy on disk.
-k, --keep-old-files
Don't replace existing files when extracting.
--keep-newer-files
Don't replace existing files that are newer than their archive copies.
--keep-directory-symlink
Don't replace existing symlinks to directories when extracting.
--no-overwrite-dir
Preserve metadata of existing directories.
--one-top-level[=DIR]
Extract all files into DIR, or, if used without argument, into a subdirectory named by the base name of the archive (minus standard compression suffixes recognizable by --auto-compress).
--overwrite
Overwrite existing files when extracting.
--overwrite-dir
Overwrite metadata of existing directories when extracting (default).
--recursive-unlink
Recursively remove all files in the directory prior to extracting it.
--remove-files
Remove files from disk 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
Verify the archive after writing it.
 

Output stream selection

--ignore-command-error
Ignore subprocess exit codes.
--no-ignore-command-error
Treat non-zero exit codes of children as error (default).
-O, --to-stdout
Extract files to standard output.
--to-command=COMMAND
Pipe extracted files to COMMAND. The argument is the pathname of an external program, optionally with command line arguments. The program will be invoked and the contents of the file being extracted supplied to it on its standard input. Additional data will be supplied via the following environment variables:
TAR_FILETYPE
Type of the file. It is a single letter with the following meaning:


        f           Regular file
        d           Directory
        l           Symbolic link
        h           Hard link
        b           Block device
        c           Character device

Currently only regular files are supported.

TAR_MODE
File mode, an octal number.
TAR_FILENAME
The name of the file.
TAR_REALNAME
Name of the file as stored in the archive.
TAR_UNAME
Name of the file owner.
TAR_GNAME
Name of the file owner group.
TAR_ATIME
Time of last access. It is a decimal number, representing seconds since the Epoch. If the archive provides times with nanosecond precision, the nanoseconds are appended to the timestamp after a decimal point.
TAR_MTIME
Time of last modification.
TAR_CTIME
Time of last status change.
TAR_SIZE
Size of the file.
TAR_UID
UID of the file owner.
TAR_GID
GID of the file owner.

Additionally, the following variables contain information about tar operation mode and the archive being processed:

TAR_VERSION
GNU tar version number.
TAR_ARCHIVE
The name of the archive tar is processing.
TAR_BLOCKING_FACTOR
Current blocking factor, i.e. number of 512-byte blocks in a record.
TAR_VOLUME
Ordinal number of the volume tar is processing (set if reading a multi-volume archive).
TAR_FORMAT
Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7.
TAR_SUBCOMMAND
A short option (with a leading dash) describing the operation tar is executing.
 

Handling of file attributes

--atime-preserve[=METHOD]
Preserve access times on dumped files, either by restoring the times after reading (METHOD=replace, this is the default) or by not setting the times in the first place (METHOD=system)
--delay-directory-restore
Delay setting modification times and permissions of extracted directories until the end of extraction. Use this option when extracting from an archive which has unusual member ordering.
--group=NAME[:GID]
Force NAME as group for added files. If GID is not supplied, NAME can be either a user name or numeric GID. In this case the missing part (GID or name) will be inferred from the current host's group database.

When used with --group-map=FILE, affects only those files whose owner group is not listed in FILE.

--group-map=FILE
Read group translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single group. It must consist of two fields, delimited by any amount of whitespace:

OLDGRP NEWGRP[:NEWGID]

OLDGRP is either a valid group name or a GID prefixed with +. Unless NEWGID is supplied, NEWGRP must also be either a valid group name or a +GID. Otherwise, both NEWGRP and NEWGID need not be listed in the system group database.

As a result, each input file with owner group OLDGRP will be stored in archive with owner group NEWGRP and GID NEWGID.

--mode=CHANGES
Force symbolic mode CHANGES for added files.
--mtime=DATE-OR-FILE
Set mtime for added files. DATE-OR-FILE is either a date/time in almost arbitrary format, or the name of an existing file. In the latter case the mtime of that file will be used.
-m, --touch
Don't extract file modified time.
--no-delay-directory-restore
Cancel the effect of the prior --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[:UID]
Force NAME as owner for added files. If UID is not supplied, NAME can be either a user name or numeric UID. In this case the missing part (UID or name) will be inferred from the current host's user database.

When used with --owner-map=FILE, affects only those files whose owner is not listed in FILE.

--owner-map=FILE
Read owner translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single UID. It must consist of two fields, delimited by any amount of whitespace:

OLDUSR NEWUSR[:NEWUID]

OLDUSR is either a valid user name or a UID prefixed with +. Unless NEWUID is supplied, NEWUSR must also be either a valid user name or a +UID. Otherwise, both NEWUSR and NEWUID need not be listed in the system user database.

As a result, each input file owned by OLDUSR will be stored in archive with owner name NEWUSR and UID NEWUID.

-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).
-s, --preserve-order, --same-order
Sort names to extract to match archive
--sort=ORDER
When creating an archive, sort directory entries according to ORDER, which is one of none, name, or inode.

The default is --sort=none, which stores archive members in the same order as returned by the operating system.

Using --sort=name ensures the member ordering in the created archive is uniform and reproducible.

Using --sort=inode reduces the number of disk seeks made when creating the archive and thus can considerably speed up archivation. This sorting order is supported only if the underlying system provides the necessary information.

 

Extended file attributes

--acls
Enable POSIX ACLs support.
--no-acls
Disable POSIX ACLs support.
--selinux
Enable SELinux context support.
--no-selinux
Disable SELinux context support.
--xattrs
Enable extended attributes support.
--no-xattrs
Disable extended attributes support.
--xattrs-exclude=PATTERN
Specify the exclude pattern for xattr keys. PATTERN is a POSIX regular expression, e.g. --xattrs-exclude='^user.', to exclude attributes from the user namespace.
--xattrs-include=PATTERN
Specify the include pattern for xattr keys. PATTERN is a POSIX regular expression.
 

Device selection and switching

-f, --file=ARCHIVE
Use archive file or device ARCHIVE. If this option is not given, tar will first examine the environment variable `TAPE'. If it is set, its value will be used as the archive name. Otherwise, tar will assume the compiled-in default. The default value can be inspected either using the --show-defaults option, or at the end of the tar --help output.

An archive name that has a colon in it specifies a file or device on a remote machine. The part before the colon is taken as the machine name or IP address, and the part after it as the file or device pathname, e.g.:

--file=remotehost:/dev/sr0

An optional username can be prefixed to the hostname, placing a @ sign between them.

By default, the remote host is accessed via the rsh(1) command. Nowadays it is common to use ssh(1) instead. You can do so by giving the following command line option:

--rsh-command=/usr/bin/ssh

The remote machine should have the rmt(8) command installed. If its pathname does not match tar's default, you can inform tar about the correct pathname using the --rmt-command option.

--force-local
Archive file is local even if it has a colon.
-F, --info-script=COMMAND, --new-volume-script=COMMAND
Run COMMAND at the end of each tape (implies -M). The command can include arguments. When started, it will inherit tar's environment plus the following variables:
TAR_VERSION
GNU tar version number.
TAR_ARCHIVE
The name of the archive tar is processing.
TAR_BLOCKING_FACTOR
Current blocking factor, i.e. number of 512-byte blocks in a record.
TAR_VOLUME
Ordinal number of the volume tar is processing (set if reading a multi-volume archive).
TAR_FORMAT
Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7.
TAR_SUBCOMMAND
A short option (with a leading dash) describing the operation tar is executing.
TAR_FD
File descriptor which can be used to communicate the new volume name to tar.

If the info script fails, tar exits; otherwise, it begins writing the next volume.

-L, --tape-length=N
Change tape after writing Nx1024 bytes. If N is followed by a size suffix (see the subsection Size suffixes below), the suffix specifies the multiplicative factor to be used instead of 1024.

This option implies -M.

-M, --multi-volume
Create/list/extract multi-volume archive.
--rmt-command=COMMAND
Use COMMAND instead of rmt when accessing remote archives. See the description of the -f option, above.
--rsh-command=COMMAND
Use COMMAND instead of rsh when accessing remote archives. See the description of the -f option, above.
--volno-file=FILE
When this option is used in conjunction with --multi-volume, tar will keep track of which volume of a multi-volume archive it is working in FILE.
 

Device blocking

-b, --blocking-factor=BLOCKS
Set record size to BLOCKSx512 bytes.
-B, --read-full-records
When listing or extracting, accept incomplete input records after end-of-file marker.
-i, --ignore-zeros
Ignore zeroed blocks in archive. Normally two consecutive 512-blocks filled with zeroes mean EOF and tar stops reading after encountering them. This option instructs it to read further and is useful when reading archives created with the -A option.
--record-size=NUMBER
Set record size. NUMBER is the number of bytes per record. It must be multiple of 512. It can can be suffixed with a size suffix, e.g. --record-size=10K, for 10 Kilobytes. See the subsection Size suffixes, for a list of valid suffixes.
 

Archive format selection

-H, --format=FORMAT
Create archive of the given format. Valid formats are:
gnu
GNU tar 1.13.x format
oldgnu
GNU format as per tar <= 1.12.
pax, posix
POSIX 1003.1-2001 (pax) format.
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 when creating PAX archives (-H pax). This option is equivalent to the -o option of the pax(1) utility.
--posix
Same as --format=posix.
-V, --label=TEXT
Create archive with volume name TEXT. If listing or extracting, 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=COMMAND
Filter data through COMMAND. It must accept the -d option, for decompression. The argument can contain command line options.
-j, --bzip2
Filter the archive through bzip2(1).
-J, --xz
Filter the archive through xz(1).
--lzip
Filter the archive through lzip(1).
--lzma
Filter the archive through lzma(1).
--lzop
Filter the archive through lzop(1).
--no-auto-compress
Do not use archive suffix to determine the compression program.
-z, --gzip, --gunzip, --ungzip
Filter the archive through gzip(1).
-Z, --compress, --uncompress
Filter the archive through compress(1).
--zstd
Filter the archive through zstd(1).
 

Local file selection

--add-file=FILE
Add FILE to the archive (useful if its name starts with a dash).
--backup[=CONTROL]
Backup before removal. The CONTROL argument, if supplied, controls the backup policy. Its valid values are:
none, off
Never make backups.
t, numbered
Make numbered backups.
nil, existing
Make numbered backups if numbered backups exist, simple backups otherwise.
never, simple
Always make simple backups

If CONTROL is not given, the value is taken from the VERSION_CONTROL environment variable. If it is not set, existing is assumed.

-C, --directory=DIR
Change to DIR before performing any operations. This option is order-sensitive, i.e. it affects all options that follow.
--exclude=PATTERN
Exclude files matching PATTERN, a glob(3)-style wildcard pattern.
--exclude-backups
Exclude backup and lock files.
--exclude-caches
Exclude contents of directories containing file CACHEDIR.TAG, except for the tag file itself.
--exclude-caches-all
Exclude directories containing file CACHEDIR.TAG and the file itself.
--exclude-caches-under
Exclude everything under directories containing CACHEDIR.TAG
--exclude-ignore=FILE
Before dumping a directory, see if it contains FILE. If so, read exclusion patterns from this file. The patterns affect only the directory itself.
--exclude-ignore-recursive=FILE
Same as --exclude-ignore, except that patterns from FILE affect both the directory and all its subdirectories.
--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
Exclude files that match patterns read from VCS-specific ignore files. Supported files are: .cvsignore, .gitignore, .bzrignore, and .hgignore.
-h, --dereference
Follow symlinks; archive and dump the files they point to.
--hard-dereference
Follow hard links; archive and dump the files they refer to.
-K, --starting-file=MEMBER
Begin at the given member in the archive.
--newer-mtime=DATE
Work on files whose data changed after the DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date.
--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
Treat each line read from a file list as if it were supplied in the command line. I.e., leading and trailing whitespace is removed and, if the resulting string begins with a dash, it is treated as tar command line option.

This is the default behavior. The --no-verbatim-files-from option is provided as a way to restore it after --verbatim-files-from option.

This option is positional: it affects all --files-from options that occur after it in, until --verbatim-files-from option or end of line, whichever occurs first.

It is implied by the --no-null option.

--null
Instruct subsequent -T options to read null-terminated names verbatim (disables special handling of names that start with a dash).

See also --verbatim-files-from.

-N, --newer=DATE, --after-date=DATE
Only store files newer than DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date.
--one-file-system
Stay in local file system when creating archive.
-P, --absolute-names
Don't strip leading slashes from file names when creating archives.
--recursion
Recurse into directories (default).
--suffix=STRING
Backup before removal, override usual suffix. Default suffix is ~, unless overridden by environment variable SIMPLE_BACKUP_SUFFIX.
-T, --files-from=FILE
Get names to extract or create from FILE.

Unless specified otherwise, the FILE must contain a list of names separated by ASCII LF (i.e. one name per line). The names read are handled the same way as command line arguments. They undergo quote removal and word splitting, and any string that starts with a - is handled as tar command line option.

If this behavior is undesirable, it can be turned off using the --verbatim-files-from option.

The --null option instructs tar that the names in FILE are separated by ASCII NUL character, instead of LF. It is useful if the list is generated by find(1) -print0 predicate.

--unquote
Unquote file or member names (default).
--verbatim-files-from
Treat each line obtained from a file list as a file name, even if it starts with a dash. File lists are supplied with the --files-from (-T) option. The default behavior is to handle names supplied in file lists as if they were typed in the command line, i.e. any names starting with a dash are treated as tar options. The --verbatim-files-from option disables this behavior.

This option affects all --files-from options that occur after it in the command line. Its effect is reverted by the --no-verbatim-files-from} option.

This option is implied by the --null option.

See also --add-file.

-X, --exclude-from=FILE
Exclude files matching patterns listed in FILE.
 

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.
 

File name matching options

These 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).
 

Informative output

--checkpoint[=N]
Display progress messages every Nth record (default 10).
--checkpoint-action=ACTION
Run ACTION on each checkpoint.
--clamp-mtime
Only set time when the file is more recent than what was given with --mtime.
--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 quoting style for file and member names. Valid values for STYLE are literal, shell, shell-always, c, c-maybe, escape, locale, clocale.
-R, --block-number
Show block number within archive with each message.
--show-omitted-dirs
When listing or extracting, list each directory that does not match search criteria.
--show-transformed-names, --show-stored-names
Show file or archive names after transformation by --strip and --transform options.
--totals[=SIGNAL]
Print total bytes after processing the archive. If SIGNAL is given, print total bytes when this signal is delivered. Allowed signals are: SIGHUP, SIGQUIT, SIGINT, SIGUSR1, and SIGUSR2. The SIG prefix can be omitted.
--utc
Print file modification times in UTC.
-v, --verbose
Verbosely list files processed. Each instance of this option on the command line increases the verbosity level by one. The maximum verbosity level is 3. For a detailed discussion of how various verbosity levels affect tar's output, please refer to GNU Tar Manual, subsection 2.5.1 "The --verbose Option".
--warning=KEYWORD
Enable or disable warning messages identified by KEYWORD. The messages are suppressed if KEYWORD is prefixed with no- and enabled otherwise.

Multiple --warning messages accumulate.

Keywords controlling general tar operation:

all
Enable all warning messages. This is the default.
none
Disable all warning messages.
filename-with-nuls
"%s: file name read contains nul character"
alone-zero-block
"A lone zero block at %s"
Keywords applicable for tar --create:
cachedir
"%s: contains a cache directory tag %s; %s"
file-shrank
"%s: File shrank by %s bytes; padding with zeros"
xdev
"%s: file is on a different filesystem; not dumped"
file-ignored
"%s: Unknown file type; file ignored"
"%s: socket ignored"
"%s: door ignored"
file-unchanged
"%s: file is unchanged; not dumped"
ignore-archive
"%s: file is the archive; not dumped"
file-removed
"%s: File removed before we read it"
file-changed
"%s: file changed as we read it"
failed-read
Suppresses warnings about unreadable files or directories. This keyword applies only if used together with the --ignore-failed-read option.
Keywords applicable for tar --extract:
existing-file
"%s: skipping existing file"
timestamp
"%s: implausibly old time stamp %s"
"%s: time stamp %s is %s s in the future"
contiguous-cast
"Extracting contiguous files as regular files"
symlink-cast
"Attempting extraction of symbolic links as hard links"
unknown-cast
"%s: Unknown file type '%c', extracted as normal file"
ignore-newer
"Current %s is newer or same age"
unknown-keyword
"Ignoring unknown extended header keyword '%s'"
decompress-program
Controls verbose description of failures occurring when trying to run alternative decompressor programs. This warning is disabled by default (unless --verbose is used). A common example of what you can get when using this warning is:

$ tar --warning=decompress-program -x -f archive.Z tar (child): cannot run compress: No such file or directory tar (child): trying gzip

This means that tar first tried to decompress archive.Z using compress, and, when that failed, switched to gzip.

record-size
"Record size = %lu blocks"
Keywords controlling incremental extraction:
rename-directory
"%s: Directory has been renamed from %s"
"%s: Directory has been renamed"
new-directory
"%s: Directory is new"
xdev
"%s: directory is on a different device: not purging"
bad-dumpdir
"Malformed dumpdir: 'X' never used"
-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.
 

Size suffixes


        Suffix    Units                   Byte Equivalent
        b         Blocks                  SIZE x 512
        B         Kilobytes               SIZE x 1024
        c         Bytes                   SIZE
        G         Gigabytes               SIZE x 1024^3
        K         Kilobytes               SIZE x 1024
        k         Kilobytes               SIZE x 1024
        M         Megabytes               SIZE x 1024^2
        P         Petabytes               SIZE x 1024^5
        T         Terabytes               SIZE x 1024^4
        w         Words                   SIZE x 2

 

RETURN VALUE

Tar exit code indicates whether it was able to successfully perform the requested operation, and if not, what kind of error occurred.
0
Successful termination.
1
Some files differ. If tar was invoked with the --compare (--diff, -d) command line option, this means that some files in the archive differ from their disk counterparts. If tar was given one of the --create, --append or --update options, this exit code means that some files were changed while being archived and so the resulting archive does not contain the exact copy of the file set.
2
Fatal error. This means that some fatal, unrecoverable error occurred.

If a subprocess that had been invoked by tar exited with a nonzero exit code, tar itself exits with that code as well. This can happen, for example, if a compression option (e.g. -z) was used and the external compressor program failed. Another example is rmt failure during backup to a remote device.  

SEE ALSO

bzip2(1), compress(1), gzip(1), lzma(1), lzop(1), rmt(8), symlink(7), xz(1), zstd(1).

Complete tar manual: run info tar or use emacs(1) info mode to read it.

Online copies of GNU tar documentation in various formats can be found at:

http://www.gnu.org/software/tar/manual  

BUG REPORTS

Report bugs to <bug-tar@gnu.org>.  

COPYRIGHT

Copyright © 2013-2019 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.


 

Index

NAME
SYNOPSIS
Traditional usage
UNIX-style usage
GNU-style usage
NOTE
DESCRIPTION
Option styles
Operation mode
OPTIONS
Operation modifiers
Overwrite control
Output stream selection
Handling of file attributes
Extended file attributes
Device selection and switching
Device blocking
Archive format selection
Compression options
Local file selection
File name transformations
File name matching options
Informative output
Compatibility options
Size suffixes
RETURN VALUE
SEE ALSO
BUG REPORTS
COPYRIGHT