Linux tar Command
Learn Linux tar Command with examples
Published
- Linux tar Command
- tar Command Syntax
- tar -czvf to Compress log files Example
- tar -czvf step by step guide
- Remove files after tar archieve compression
- tar -tvf to view tar file content
- Extract a tar file archive
- Use “&” with tar command to keep execute in the background
- zgrep Command to Search Inside tar File without Decompress
- Usage of tar files
Linux tar Command
In Linux we use “tar” command for creating & extracting archive files. It’s short for Tape Archive.
An archive file is a compressed file containing one or multiple files bundled together for more accessible storage and portability.
tar Command Syntax
~$ tar [options][archive-file] [file or dir to be archived]
| Argument | Description |
| -c | We use this flag whenever we need to create a new archive. |
| -z | When we specify this flag; it means that archive will be created using gzip compression. |
| -v | Providing the -v flag shows details of the files compressed. |
| -f | Archive file names are mapped using the -f flag. |
| -x | We use this flag when files need to be extracted from an archive. |
tar -czvf to Compress log files Example
~$ tar -czvf logs.tar.gz *
tar -czvf step by step guide
~$ mkdir logs
~$ cd logs
~$ touch log1
~$ touch log2
~$ touch log3
~$ tar -czvf logs.tar.gz *
~$ ls -l
# tar -czvf will create logs.tar.gz.
Let’s break down this command and look into each flag.
| Argument | Description |
| -c | to creating and archive. |
| -z | for using gzip compression. |
| -v | for providing details of the files that have been archived. |
| -f | for creating an archive with the name 'logs_archive.tar.gz' as supplied in the command above. |
Remove files after tar archieve compression
Let’s say we don’t want to keep the original files after creating an archive. For that, we can use the –remove-files flag.
~$ tar -czvf logs.tar.gz * --remove-files
tar -tvf to view tar file content
If you need to view the contents of an tar archieve file without actually extracting it then Use -t flag.
~$ tar -tvf logs.tar.gz
# -t flag specifies that we need to only view the contents of the archive.
# -f specifies the filename
# -v displays the detailed contents.
Extract a tar file archive
To extract files from an archive, you use the -x flag like this:
~$ tar -xzvf logs.tar.gz
| Argument | Description |
| -x | extracting and archive. |
| -z | specifies that the archive is gzip. |
| -v | providing details of the files that have been archived. |
| -f | extracting from the archive named 'logs_archive.tar.gz'. |
Use “&” with tar command to make sure that a long time to execute can continue in the background
~$ tar -xzvf logs.tar.gz &
Adding files to an archive and extracting an archive can take a while. To keep the commands running in the background while you keep working, pair the command with & like this.
zgrep Command to Search Inside tar File without Decompress
You might still need to access certain files once they’re archived. We can search for a string in an archive using the below command.
~$ zgrep -Hna 'string-content-to-search' logs.tar.gz
| Argument | Description |
| -H | lists the file name that contains the match. |
| -n | displays the line number that contains the matched string. |
| -a | treats all files as text files. |
Usage of tar files
One of main advantage we take from tar archieve file is to schedule file compression via cron jobs to automate disk cleaning. File compression helps us save time and resources when sharing files. Servers can utilize to rotating and archiving huge log files.
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 let‐
ters and all subsequent arguments supply arguments to those op‐
tions 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 argu‐
ments: file or archive member names.
For example, the c option requires creating the archive, the v op‐
tion requests the verbose operation, and the f option takes an ar‐
gument 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 a.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 com‐
mand 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 to‐
gether after a single dash, e.g. -vkp. Options that take argu‐
ments (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 a.tar /etc
or
tar -c -v -f a.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 ini‐
tial letters, provided that this does not create ambiguity. Argu‐
ments 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 a.tar --verbose /etc
or (abbreviating some options):
tar --cre --file=a.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 argu‐
ments 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 unus‐
able with non-GNU implementations of tar. Notice also that
when more than one archive is given, the members from ar‐
chives other than the first one will be accessible in the
resulting archive only if using the -i (--ignore-zeros) op‐
tion.
Compressed archives cannot be concatenated.
-c, --create
Create a new archive. Arguments supply the names of the
files to be archived. Directories are archived recur‐
sively, unless the --no-recursion option is given.
-d, --diff, --compare
Find differences between archive and file system. The ar‐
guments are optional and specify archive members to com‐
pare. If not given, the current working directory is as‐
sumed.
--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 al‐
lowed.
--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 infor‐
mation 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 ar‐
chive, it will be created and all files will be added to
the resulting archive (the level 0 dump). To create incre‐
mental 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 re‐
quirements. 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 appli‐
cable.
-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 recogni‐
tion 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 ar‐
chives.
--no-seek
Assume the archive is not seekable.
--occurrence[=N]
Process only the Nth occurrence of each file in the ar‐
chive. 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 com‐
mand 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 sys‐
tems as DBM). When given this option, tar attempts to de‐
termine 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 ar‐
chive copies.
--keep-directory-symlink
Don't replace existing symlinks to directories when ex‐
tracting.
--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 ex‐
tracting 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 path‐
name 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
output. 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, repre‐
senting 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 opera‐
tion 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 de‐
fault) or by not setting the times in the first place
(METHOD=system)
--delay-directory-restore
Delay setting modification times and permissions of ex‐
tracted 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 sup‐
plied, 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 ig‐
nored. 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 ex‐
isting 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 sup‐
plied, 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 ig‐
nored. 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 su‐
peruser)
--preserve
Same as both -p and -s.
--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 cre‐
ated 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 ar‐
chive name. Otherwise, tar will assume the compiled-in de‐
fault. 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, plac‐
ing a @ sign between them.
By default, the remote host is accessed via the rsh(1) com‐
mand. 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 in‐
stalled. 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 com‐
mand 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-vol‐
ume, 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 read‐
ing 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 ex‐
tracting, 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 pro‐
gram.
-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 VER‐
SION_CONTROL environment variable. If it is not set, ex‐
isting is assumed.
-C, --directory=DIR
Change to DIR before performing any operations. This op‐
tion 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 sup‐
plied 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 --verba‐
tim-files-from option.
This option is positional: it affects all --files-from op‐
tions 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 ctime 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 suf‐
fix is ~, unless overridden by environment variable SIM‐
PLE_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 argu‐
ments. 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 predi‐
cate.
--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 af‐
ter 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 extrac‐
tion.
--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, es‐
cape, 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.
--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 direc‐
tories. 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 pro‐
grams. 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 ar‐
chive.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 purg‐
ing"
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 per‐
form the requested operation, and if not, what kind of error oc‐
curred.
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 er‐
ror 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 hap‐
pen, 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.