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tar(1)			    General Commands Manual			tar(1)

NAME
       tar - tape file archiver

SYNOPSIS
       [arg ...]  [file	|

DESCRIPTION
       The  command saves and restores archives	of files on a magnetic tape, a
       flexible	disk, or a regular file.  The default archive file is See  the
       option below.  Its actions are controlled by the	key argument.

   Arguments
       key	     is	a string of characters containing exactly one function
		     letter and	zero or	more function modifiers, specified  in
		     any  order.  Whitespace is	not permitted in key.  The key
		     string can	be preceded by a hyphen	as when	specifying op-
		     tions in other HP-UX commands, but	it is not necessary.

       arg ...	     The  and  function	modifiers each require an arg argument
		     (see below).  If both and are specified, the order	of the
		     arg  arguments must match the order of the	modifiers.  If
		     specified,	the arg	arguments must be separated  from  the
		     key and each other	by whitespace.

       file	     specifies	a  file	being saved or restored.  If file is a
		     directory name, it	refers to the files and	 (recursively)
		     the subdirectories	contained in that directory.

       causes	     to	 perform  a  to	 directory (see	chdir(2)).  Subsequent
		     file and arguments	are relative to	directory.   This  al-
		     lows  multiple directories	not related by a close or com-
		     mon parent	to  be	archived  using	 short	relative  path
		     names.

       The  value of file is stored in the archive.  The value of directory is
       not stored.

   Function Keys
       The function portion of the key is specified by exactly one of the fol-
       lowing letters:

	      Create a new archive.
		     Write  from  the  beginning of the	archive	instead	of ap-
		     pending after the last file.  Any previous	information in
		     the archive is overwritten.

	      Add the named
		     file to the end of	the archive.  The same blocking	factor
		     used to create the	archive	must be	used to	append to  it.
		     This option cannot	be used	if the archive is a tape.

	      List the names of	all the	files in the archive.
		     Adding  the function modifier expands this	listing	to in-
		     clude the file modes and owner numbers.  The names	of all
		     files are listed each time	they occur on the tape.

	      Add any named
		     file  to  the archive if it is not	already	present	or has
		     been modified since it was	last written in	 the  archive.
		     The  same blocking	factor used to create the archive must
		     be	used to	update it.

	      Extract the named
		     file from the archive and restore it to the system.  If a
		     named  file matches a directory whose contents were writ-
		     ten to the	archive, this directory	is  (recursively)  ex-
		     tracted.	If  a named file on tape does not exist	on the
		     system, the file is created as follows:

			o  The user, group, and	other protections are restored
			   from	the tape.

			o  The modification time is restored from the tape un-
			   less	the function modifier is specified.

			o  The file user ID and	group ID are normally those of
			   the restoring process.

			o  The	set-user-ID, set-group-ID, and sticky bits are
			   not set automatically.  The and function  modifiers
			   control  the	 restoration  of protection; see below
			   for more details.

		     If	the files exist, their modes are not changed, but  the
		     set-user-id,  set-group-id	 and  sticky bits are cleared.
		     If	no file	argument is given, the entire content  of  the
		     archive  is  extracted.   Note that if several files with
		     the same name are on the archive, the last	one overwrites
		     all earlier ones.

   Function Modifier Keys
       The  following  function	modifiers can be used in addition to the func-
       tion letters listed above (note that some  modifiers  are  incompatible
       with some functions):

	      Suppress warning messages	that
		     did  not  archive	a  file's access control list.	By de-
		     fault, writes a warning message for each  file  with  op-
		     tional ACL	entries.

	      Use the next
		     arg  argument as the blocking factor for archive records.
		     The default is 20;	the maximum is at least	20.   However,
		     if	 the  modifier	is used	to specify standard input, the
		     default blocking factor is	1.

		     The blocking  factor  is  determined  automatically  when
		     reading  nine-track  tapes	(key letters and On nine-track
		     tapes, the	physical tape record length is the same	as the
		     block  size.   The	 block	size is	defined	as the logical
		     record size times the blocking factor (number of  logical
		     records per block).

		     The blocking factor must be specified when	reading	flexi-
		     ble disks and cartridge tapes if they were	written	with a
		     blocking factor other than	the default.

		     If	 a  file  is read using	a blocking factor not equal to
		     the one used when the file	was written, an	error may  oc-
		     cur at the	end of the file	but there may or may not be an
		     actual error in the read.	To  prevent  this  problem,  a
		     blocking  factor of can be	used, although performance may
		     be	reduced	somewhat.

		     writes logical records of 512 bytes, independent  of  how
		     logical  records  may  be defined elsewhere by other pro-
		     grams (such as variable-length records (lines) within  an
		     ASCII text	file).

	      Fail  if	the  extent  attributes	are present in the files to be
	      archived.
		     If	fails for this reason, the partially created  destina-
		     tion file is not be removed.

	      Use the next
		     arg  argument  as	the name of the	archive	instead	of the
		     default, If the name of the file is  writes  to  standard
		     output  or	reads from standard input, whichever is	appro-
		     priate, and the default blocking factor becomes 1.	 Thus,
		     can  be used as the head or tail of a pipeline (see EXAM-
		     PLES).

	      Force  to	follow symbolic	links as if they were normal files  or
		     directories.  Normally, does not follow symbolic links.

	      Tell   to	 complain if it	cannot resolve all of the links	to the
		     files being saved.	 If is not specified,  no  error  mes-
		     sages are printed.

	      Tell   not  to  restore the modification time written on the ar-
		     chive.  The modification time of the  file	 will  be  the
		     time of extraction.

	      Write a POSIX format archive.
		     This  format allows file names of up to 256 characters in
		     length, and correctly archives and	restores the following
		     file  types:  regular  files, character and block special
		     devices, links, symbolic  links,  directories,  and  FIFO
		     special files.  It	also stores the	user and group name of
		     each file and attempts to use these  names	 to  determine
		     the user-ID and group-ID of a file	when restoring it with
		     the function modifier.  This is the default format.

	      Suppress writing certain directory information that  older  ver-
	      sions of
		     cannot  handle  on	 input.	  normally  writes information
		     specifying	owners and modes of  directories  in  the  ar-
		     chive.  Earlier versions of when encountering this	infor-
		     mation, give error	messages of the	form:

		     When is used for reading, it causes the extracted file to
		     take  on  the  user and group IDs of the user running the
		     program rather than those on the tape.  This is  the  de-
		     fault for the ordinary user and can be overridden,	to the
		     extent that system	protections allow, by using the	 func-
		     tion modifier.

	      Write a pre-POSIX	format archive.

	      Cause  file  to be restored to the original modes	and ownerships
		     written on	the archive, if	possible.  This	is the default
		     for  the superuser, and can be overridden by the function
		     modifier.	If system  protections	prevent	 the  ordinary
		     user  from	executing the error is ignored,	and the	owner-
		     ship is  set  to  that  of	 the  restoring	 process  (see
		     chown(2)).	 The set-user-id, set-group-id,	and sticky bit
		     information are restored as allowed  by  the  protections
		     defined by	if the operation above succeeds.

	      nd     Specify  a	 particular nine-track tape drive and density,
		     where n is	a tape drive number: and d is the  density:  =
		     low  (800	bpi);  = medium	(1600 bpi); = high (6250 bpi).
		     This modifier selects the drive on	which  the  nine-track
		     tape is mounted.  The default is

	      Normally,
		     does  its work silently.  The (verbose) function modifier
		     causes to type the	name of	each file it treats,  preceded
		     by	 the  function	letter.	 With the function, gives more
		     information about the archive entries than	just the name.

	      Same as the
		     function modifier except that,  when  using  the  option,
		     also  prints  out	a  letter  indicating  the type	of the
		     archived file.

	      Cause  to	print the action being taken, followed by the name  of
		     the  file,	then wait for the user's confirmation.	If the
		     user answers the action is	performed.   Any  other	 input
		     means "no".

       When  end-of-tape  is  reached, prompts the user	for a new special file
       and continues.

       If a nine-track tape drive is used as the output	 device,  it  must  be
       configured in Berkeley-compatibility mode (see mt(7)).

       The  function modifiers specify the format in which writes the archive.
       Upon extraction,	can read either	format,	 regardless  of	 the  function
       modifiers used.

EXTERNAL INFLUENCES
   Environment Variables
       determines the format and contents of date and time strings output when
       listing the contents of an archive with the option.

       determines the language equivalent of (for yes/no queries).

       If is not specified in the environment or is set	to the	empty  string,
       the value of is used as the default.

       If  is  not specified or	is set to the empty string, it defaults	to "C"
       (see lang(5)).

       If any internationalization variable contains an	invalid	 setting,  be-
       haves as	if all internationalization variables are set to "C".  See en-
       viron(5).

   International Code Set Support
       Single- and multibyte character code sets are supported.

ERRORS
       issues  self-explanatory	 messages  about  bad  key  characters,	  tape
       read/write  errors,  and	 if not	enough memory is available to hold the
       link tables.

EXAMPLES
       Create a	new archive on and copy	and onto it, using the default	block-
       ing  factor  of	20.  The key is	made up	of one function	letter and two
       function	modifiers and

       Archive files from and

       Use in a	pipeline to  copy  the	entire	file  system  hierarchy	 under
       fromdir to todir:

       Archive all files and directories in directory in the current directory
       to a file called	also in	the current directory:

WARNINGS
       Because of industry standards and interoperability goals, does not sup-
       port  the  archival  of	files  larger  than  2GB  or  files  that have
       user/group IDs greater than 60K.	 Files	with  user/group  IDs  greater
       than  60K are archived and restored under the user/group	ID of the cur-
       rent process.

       The default format has changed from beginning with HP-UX	Release	8.0.

       Due to internal limitations in the header structure, not	all file names
       of  fewer than 256 characters fit when using the	function modifier.  If
       a file name does	not fit, prints	a message and  does  not  archive  the
       file.

       Link  names are still limited to	100 characters when using the function
       modifier.

       There is	no way to ask for the n-th occurrence of a file.

       Tape errors are handled ungracefully.

       The function key	can be slow.

       If the archive is a file	on disk, flexible disk,	or cartridge tape, and
       if the blocking factor specified	on output is not the default, the same
       blocking	factor must be specified on input, because the blocking	factor
       is  not explicitly stored in the	archive.  Updating or appending	to the
       archive without following this rule can destroy it.

       Some previous versions of have claimed to support the selective listing
       of  file	 names using the function key with a list.  This appears to be
       an error	in the documentation because the capability does not appear in
       the original source code.

       There  is  no  way to restore an	absolute path name to a	relative posi-
       tion.

       always pads information written to an archive up	to the	next  multiple
       of  the block size.  Therefore, if you are creating a small archive and
       write out one block of information, reports that	one block was written,
       but the actual size of the archive might	be larger if the function mod-
       ifier is	used.

       Note that is not	the same as

       Do not create archives on block special devices.	 Attempting to	do  so
       can causes excessive wear, leading to premature drive hardware failure.

DEPENDENCIES
   Series 700/800
       The  and	 function  keys	 are  not supported on QIC or 8mm devices.  If
       these options are used with QIC or 8mm devices, fails and displays  the
       message:

AUTHOR
       was  developed by AT&T, the University of California, Berkeley, HP, and
       POSIX.

FILES
SEE ALSO
       ar(1), cpio(1), acl(5), mt(7).

STANDARDS CONFORMANCE
									tar(1)

NAME | SYNOPSIS | DESCRIPTION | EXTERNAL INFLUENCES | ERRORS | EXAMPLES | WARNINGS | DEPENDENCIES | AUTHOR | FILES | SEE ALSO | STANDARDS CONFORMANCE

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