tar(1) - OpenBSD manual pages (original) (raw)
NAME
tar —tape archiver
SYNOPSIS
| tar | {crtux}[014578beFfHhjLmNOoPpqsvwXZz] [blocking-factor | format | archive | replstr] [-C directory] [-I file] [file ...] |
|---|
| tar | {-crtux} [-014578eHhjLmNOoPpqvwXZz] [-b blocking-factor] [-C directory] [-F format] [-f archive] [-I file] [-s replstr] [file ...] |
|---|
DESCRIPTION
The tar command creates, adds files to, or extracts files from an archive file in “tar” format. A tar archive is often stored on a magnetic tape, but can be stored equally well on a floppy, CD-ROM, or in a regular disk file.
In the first (legacy) form, all option flags except for-C and -I must be contained within the first argument to tar and must not be prefixed by a hyphen (‘-’). Option arguments, if any, are processed as subsequent arguments to tar and are processed in the order in which their corresponding option flags have been presented on the command line.
In the second and preferred form, option flags may be given in any order and are immediately followed by their corresponding option argument values.
One of the following flags must be present:
Create new archive, or overwrite an existing archive, adding the specified files to it.
Append the named new files to existing archive. Note that this will only work on media on which an end-of-file mark can be overwritten.
List contents of archive. If any files are named on the command line, only those files will be listed. The file arguments may be specified as glob patterns (seeglob(7) for more information), in which case tar will list all archive members that match each pattern.
Alias for -r.
Extract files from archive. If any files are named on the command line, only those files will be extracted from the archive. Thefile arguments may be specified as glob patterns (see glob(7) for more information), in which case tar will extract all archive members that match each pattern.
If more than one copy of a file exists in the archive, later copies will overwrite earlier copies during extraction. The file mode and modification time are preserved if possible. The file mode is subject to modification by theumask(2).
In addition to the flags mentioned above, any of the following flags may be used:
-b blocking-factor
Set blocking factor to use for the archive. tar uses 512-byte blocks. The default is 20, the maximum is 126. Archives with a blocking factor larger than 63 violate the POSIX standard and will not be portable to all systems.
-C directory
This is a positional argument which sets the working directory for the following files. When extracting, files will be extracted into the specified directory; when creating, the specified files will be matched from the directory.
Stop after the first error.
-F format
Specify the output archive format, with the default format beingpax. tar currently supports the following formats:
The old binary cpio format. The default blocksize for this format is 5120 bytes. This format is not very portable and should not be used when other formats are available. Inode and device information about a file (used for detecting file hard links by this format), which may be truncated by this format, is detected by tar and is repaired.
The extended cpio interchange format specified in theIEEE Std 1003.2 (“POSIX.2”) standard. The default blocksize for this format is 5120 bytes. Inode and device information about a file (used for detecting file hard links by this format), which may be truncated by this format, is detected by tar and is repaired.
The System V release 4 cpio. The default blocksize for this format is 5120 bytes. Inode and device information about a file (used for detecting file hard links by this format), which may be truncated by this format, is detected by tar and is repaired.
The System V release 4 cpio with file CRC checksums. The default blocksize for this format is 5120 bytes. Inode and device information about a file (used for detecting file hard links by this format), which may be truncated by this format, is detected bytar and is repaired.
The old BSD tar format as found in4.3BSD. The default blocksize for this format is 10240 bytes. Pathnames stored by this format must be 100 characters or less in length. Only regular files, hard links, soft links, and directories will be archived (other file system types are not supported). For backwards compatibility with even older tar formats, see the description for -o.
The extended tar interchange format specified in theIEEE Std 1003.2 (“POSIX.2”) standard. The default blocksize for this format is 10240 bytes. Filenames stored by this format must be 100 characters or less in length; the total pathname must be 256 characters or less.
The pax interchange format specified in the IEEE Std 1003.1-2001 (“POSIX.1”) standard. The default blocksize for this format is 5120 bytes.
tar will detect and report any file that it is unable to store or extract as the result of any specific archive format restrictions. The individual archive formats may impose additional restrictions on use. Typical archive format restrictions include (but are not limited to): file pathname length, file size, link pathname length, and the type of the file.
-f archive
Read from or write to archive. A hyphen (-) can be used to represent standard input or output. The default is/dev/rst0. See also theTAPE environment variable.
Follow symlinks given on the command line only.
Follow symbolic links as if they were normal files or directories. In extract mode this means that a directory entry in the archive will not overwrite an existing symbolic link, but rather what the link ultimately points to.
-I file
This is a positional argument which reads the names of files to archive or extract from the given file, one per line.
Compress archive using bzip2. The bzip2 utility must be installed separately.
Synonym for the -h option.
Do not preserve modification time.
Use only the numeric UID and GID values when creating or extracting an archive.
Write old-style (non-POSIX) archives.
Don't write directory information that the older (V7) styletar is unable to decode. This implies the-O flag.
Do not strip leading slashes (‘/’) from pathnames. The default is to strip leading slashes.
Preserve user and group ID as well as file mode regardless of the currentumask(2). The setuid and setgid bits are only preserved if the user and group ID could be preserved. Only meaningful in conjunction with the-x flag.
Select the first archive member that matches eachfile operand. No more than one archive member is matched for each file. When members of type directory are matched, the file hierarchy rooted at that directory is also matched.
-s replstr
Modify the archive member names according to the substitution expressionreplstr, using the syntax of theed(1) utility regular expressions. file arguments may be given to restrict the list of archive members to those specified.
The format of these regular expressions is
/old/new/[gp]
As in ed(1), old is a basic regular expression (see re_format(7)) and new can contain an ampersand (‘&’), ‘\_n_’ (where_n_ is a digit) back-references, or subexpression matching. The old string may also contain newline characters. Any non-null character can be used as a delimiter (‘/’ is shown here). Multiple-s expressions can be specified. The expressions are applied in the order they are specified on the command line, terminating with the first successful substitution.
The optional trailing g continues to apply the substitution expression to the pathname substring, which starts with the first character following the end of the last successful substitution. The first unsuccessful substitution stops the operation of the g option. The optional trailingp will cause the final result of a successful substitution to be written to standard error in the following format:
File or archive member names that substitute to the empty string are not selected and will be skipped.
Verbose operation mode. If -v is specified multiple times or if the -t option is also specified, tar will use a long format for listing files, similar to ls(1) -l.
Interactively rename files. This option causes tar to prompt the user for the filename to use when storing or extracting files in an archive.
Do not cross mount points in the file system.
Compress archive usingcompress(1).
Compress archive using gzip(1).
The options [-014578] can be used to select one of the compiled-in backup devices,/dev/rstN.
ENVIRONMENT
Path in which to store temporary files.
Default tape device to use instead of /dev/rst0. If set to hyphen (‘-’), standard output is used.
FILES
/dev/rst0
default archive name
EXIT STATUS
The tar utility exits with one of the following values:
0
All files were processed successfully.
1
An error occurred.
EXAMPLES
Create an archive on the default tape drive, containing the files named bonvole and sekve:
$ tar c bonvole sekve
Create a gzip(1) compressed archive, calledforiru.tar.gz, containing the filesbonvole and sekve:
$ tar czf foriru.tar.gz bonvole sekve
Verbosely create an archive, calledbackup.tar.gz, of all files matching the shellglob(7) function *.c:
$ tar cvzf backup.tar.gz *.c
Verbosely list, but do not extract, all files ending in.jpeg from a compressed archive namedbackup.tar.gz. Note that the glob pattern has been quoted to avoid expansion by the shell:
$ tar tvzf backup.tar.gz '*.jpeg'
Verbosely extract an archive, calledfoo.tar.gz, to the directory/var/foo:
$ tar xvzf foo.tar.gz -C /var/foo
For more detailed examples, seepax(1).
DIAGNOSTICS
Whenever tar cannot create a file or a link when extracting an archive or cannot find a file while writing an archive, or cannot preserve the user ID, group ID, file mode, or access and modification times when the -p option is specified, a diagnostic message is written to standard error and a non-zero exit value will be returned, but processing will continue. In the case wheretar cannot create a link to a file,tar will not create a second copy of the file.
If the extraction of a file from an archive is prematurely terminated by a signal or error, tar may have only partially extracted the file the user wanted. Additionally, the file modes of extracted files and directories may have incorrect file bits, and the modification and access times may be wrong.
If the creation of an archive is prematurely terminated by a signal or error, tar may have only partially created the archive, which may violate the specific archive format specification.
SEE ALSO
HISTORY
A tar command first appeared inVersion 7 AT&T UNIX.
Keith Muller at the University of California, San Diego.
CAVEATS
The -j and -L flags are not portable to other versions of tar where they may have a different meaning.