paxtar(1)
NAME
paxtar --- tape archiver
SYNOPSIS
paxtar {crtux}[014578AabefHhJjLmNOoPRSpqsvwXZz]
[blocking-factor | archive | replstr] [-C directory] [-I file]
[file ...]
paxtar {-crtux} [-014578AaeHhJjLmNOoPpqRSvwXZz] [-b blocking-factor]
[-C directory] [-f archive] [-I file] [-M flag] [-s replstr]
[file ...]
DESCRIPTION
The paxtar 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 paxtar and must not be prefixed by
a hyphen ('-'). Option arguments, if any, are processed as subsequent
arguments to paxtar 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:
-c Create new archive, or overwrite an existing archive, adding the
specified files to it.
-r 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.
-t 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 (see glob(3) for more information), in
which case paxtar will list all archive members that match each
pattern.
-u Alias for -r.
-x Extract files from archive. If any files are named on the
command line, only those files will be extracted from the
archive. The file arguments may be specified as glob patterns
(see glob(3) for more information), in which case paxtar 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 the umask(2).
In addition to the flags mentioned above, any of the following flags may
be used:
-A Write Unix Archiver libraries instead of tape archives.
-a Guess the compression utility based on the archive filename.
Inability to guess will result in quietly not using any
compression. This option only exists for semi-compatibility with
GNU tar; it is strongly recommended to archive to stdout and pipe
into an external compression utility with appropriate arguments
instead:
tar -cf - foo | xz -2e >foo.txz
-b blocking-factor
Set blocking factor to use for the archive. paxtar 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.
-e Stop after the first error.
-f archive
Filename where the archive is stored. Defaults to /dev/rst0. If
set to hyphen ('-') standard output is used. See also the TAPE
environment variable.
-H Follow symlinks given on the command line only.
-h 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.
-J Use the xz utility to compress the archive.
-j Use the bzip2 utility to compress the archive.
-L Synonym for the -h option.
-M flag
Configure the archive normaliser. flag is either a numeric value
compatible to strtonum(3) which is directly stored in the flags
word, or one of the following values, optionally prefixed with
"no-" to turn them off:
inodes 0x0001: Serialise inodes, zero device info.
(cpio, sv4cpio, sv4crc)
links 0x0002: Store content of hard links only once.
(cpio, sv4cpio, sv4crc)
mtime 0x0004: Zero out the file modification time.
(ar, cpio, sv4cpio, sv4crc, ustar)
uidgid 0x0008: Set owner to 0:0 (root:wheel).
(ar, cpio, sv4cpio, sv4crc, ustar)
verb 0x0010: Debug this option.
debug 0x0020: Debug file header storage.
lncp 0x0040: Extract hard links by copy if link fails.
numid 0x0080: Use only numeric uid and gid values.
(ustar)
gslash 0x0100: Append a slash after directory names.
(ustar)
set 0x0003: Keep ownership and mtime intact.
dist 0x008B: Clean everything except mtime.
norm 0x008F: Clean everything.
root 0x0089: Clean owner and device information.
When creating an archive and verbosely listing output, these
normalisation operations are not reflected in the output, because
they are made only after the output has been shown.
This option is only implemented for the ar, cpio, sv4cpio,
sv4crc, and ustar file format writing routines.
-m Do not preserve modification time.
-N Same as -M numid.
-O If reading, extract files to standard output.
If writing, write old-style (non-POSIX) archives.
-o If writing, write old-style (non-POSIX) archives. Don't write
directory information that the older (V7) style tar is unable to
decode.
-P For security reasons, paxtar skips pathnames containing dotdot
("..") components and strips leading slashes ('/') from pathnames
by default; this option disables that behaviour.
-p Preserve user and group ID as well as file mode regardless of the
current umask(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.
-q Select the first archive member that matches each file 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.
-R Write SysVR4 CPIO files instead of tar or POSIX ustar files.
Serialise inode numbers, zero out device information. The file
content of hard links is stored only once.
-S Write SysVR4 CPIO files with CRC instead of tar or POSIX ustar
files. Serialise inode numbers, zero out device information.
The file content of hard links is stored only once.
-s replstr
Modify the archive member names according to the substitution
expression replstr, using the syntax of the ed(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 trailing p will cause the final result of a
successful substitution to be written to standard error in the
following format:
original-pathname >> new-pathname
File or archive member names that substitute to the empty string
are not selected and will be skipped.
-v Verbose operation mode.
-w Interactively rename files. This option causes paxtar to prompt
the user for the filename to use when storing or extracting files
in an archive.
-X Do not cross mount points in the file system.
-Z Use the compress(1) utility to compress the archive.
-z Use the gzip(1) utility to compress the archive.
The options [-014578] can be used to select one of the compiled-in backup
devices, /dev/rstN.
ENVIRONMENT
TMPDIR Path in which to store temporary files.
TAPE 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 paxtar 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:
$ paxtar c bonvole sekve
Output a gzip(1) compressed archive containing the files bonvole and
sekve to a file called foriru.tar.gz:
$ paxtar zcf foriru.tar.gz bonvole sekve
Verbosely create an archive, called backup.tar.gz, of all files matching
the shell glob(3) function *.c:
$ paxtar zcvf backup.tar.gz *.c
Verbosely list, but do not extract, all files ending in .jpeg from a
compressed archive named backup.tar.gz. Note that the glob pattern has
been quoted to avoid expansion by the shell:
$ paxtar tvzf backup.tar.gz '*.jpeg'
For more detailed examples, see pax(1).
DIAGNOSTICS
Whenever paxtar 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 where paxtar cannot create a link to a file, unless -M lncp
is given, paxtar 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, paxtar 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, paxtar may have only partially created the archive, which may
violate the specific archive format specification.
SEE ALSO
ar(1), cpio(1), pax(1), paxcpio(1), tar(1), deb(5)
HISTORY
A tar command first appeared in Version 7 AT&T UNIX.
AUTHORS
Keith Muller at the University of California, San Diego. MirOS
extensions by
mirabilos <m@mirbsd.org>.
CAVEATS
The flags -AaJjLMNRS are not portable to other implementations of tar
where they may have a different meaning or not exist at all.
BUGS
The pax file format is not yet supported.
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