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PAX(1)			FreeBSD	General	Commands Manual			PAX(1)

NAME
     pax -- read and write file	archives and copy directory hierarchies

SYNOPSIS
     pax [-cdnvz] [-f archive] [-s replstr] ...	[-U user] ... [-G group] ...
	 [-T [from_date] [,to_date]] ... [pattern ...]
     pax -r [-cdiknuvzDYZ] [-f archive]	[-o options] ... [-p string] ...
	 [-s replstr] ... [-E limit] [-U user] ... [-G group] ... [-T
	 [from_date] [,to_date]] ... [pattern ...]
     pax -w [-dituvzHLPX] [-b blocksize] [[-a] [-f archive]] [-x format]
	 [-s replstr] ... [-o options] ... [-U user] ... [-G group] ...
	 [-B bytes] [-T	[from_date] [,to_date] [/[c][m]]] ... [file ...]
     pax -r -w [-diklntuvDHLPXYZ] [-p string] ... [-s replstr] ... [-U user]
	 ... [-G group]	... [-T	[from_date] [,to_date] [/[c][m]]] ...
	 [file ...] directory

DESCRIPTION
     The pax utility will read,	write, and list	the members of an archive
     file, and will copy directory hierarchies.	 These operations are indepen-
     dent of the specific archive format, and support a	wide variety of	dif-
     ferent archive formats.  A	list of	supported archive formats can be found
     under the description of the -x option.

     The presence of the -r and	the -w options specifies which of the follow-
     ing functional modes pax will operate under: list,	read, write, and copy.

     <none>  List.  Write to standard output a table of	contents of the	mem-
	     bers of the archive file read from	standard input,	whose path-
	     names match the specified patterns.  The table of contents	con-
	     tains one filename	per line and is	written	using single line
	     buffering.

     -r	     Read.  Extract the	members	of the archive file read from the
	     standard input, with pathnames matching the specified patterns.
	     The archive format	and blocking is	automatically determined on
	     input.  When an extracted file is a directory, the	entire file
	     hierarchy rooted at that directory	is extracted.  All extracted
	     files are created relative	to the current file hierarchy.	The
	     setting of	ownership, access and modification times, and file
	     mode of the extracted files are discussed in more detail under
	     the -p option.

     -w	     Write.  Write an archive containing the file operands to standard
	     output using the specified	archive	format.	 When no file operands
	     are specified, a list of files to copy with one per line is read
	     from standard input.  When	a file operand is also a directory,
	     the entire	file hierarchy rooted at that directory	will be
	     included.

     -r	-w   Copy.  Copy the file operands to the destination directory.  When
	     no	file operands are specified, a list of files to	copy with one
	     per line is read from the standard	input.	When a file operand is
	     also a directory the entire file hierarchy	rooted at that direc-
	     tory will be included.  The effect	of the copy is as if the
	     copied files were written to an archive file and then subse-
	     quently extracted,	except that there may be hard links between
	     the original and the copied files (see the	-l option below).

	     Warning: The destination directory	must not be one	of the file
	     operands or a member of a file hierarchy rooted at	one of the
	     file operands.  The result	of a copy under	these conditions is
	     unpredictable.

     While processing a	damaged	archive	during a read or list operation, pax
     will attempt to recover from media	defects	and will search	through	the
     archive to	locate and process the largest number of archive members pos-
     sible (see	the -E option for more details on error	handling).

OPERANDS
     The directory operand specifies a destination directory pathname.	If the
     directory operand does not	exist, or it is	not writable by	the user, or
     it	is not of type directory, pax will exit	with a non-zero	exit status.

     The pattern operand is used to select one or more pathnames of archive
     members.  Archive members are selected using the pattern matching nota-
     tion described by fnmatch(3).  When the pattern operand is	not supplied,
     all members of the	archive	will be	selected.  When	a pattern matches a
     directory,	the entire file	hierarchy rooted at that directory will	be
     selected.	When a pattern operand does not	select at least	one archive
     member, pax will write these pattern operands in a	diagnostic message to
     standard error and	then exit with a non-zero exit status.

     The file operand specifies	the pathname of	a file to be copied or
     archived.	When a file operand does not select at least one archive mem-
     ber, pax will write these file operand pathnames in a diagnostic message
     to	standard error and then	exit with a non-zero exit status.

OPTIONS
     The following options are supported:

     -r	   Read	an archive file	from standard input and	extract	the specified
	   files.  If any intermediate directories are needed in order to
	   extract an archive member, these directories	will be	created	as if
	   mkdir(2) was	called with the	bitwise	inclusive OR of	S_IRWXU,
	   S_IRWXG, and	S_IRWXO	as the mode argument.  When the	selected ar-
	   chive format	supports the specification of linked files and these
	   files cannot	be linked while	the archive is being extracted,	pax
	   will	write a	diagnostic message to standard error and exit with a
	   non-zero exit status	at the completion of operation.

     -w	   Write files to the standard output in the specified archive format.
	   When	no file	operands are specified,	standard input is read for a
	   list	of pathnames with one per line without any leading or trailing
	   <blanks>.

     -a	   Append files	to the end of an archive that was previously written.
	   If an archive format	is not specified with a	-x option, the format
	   currently being used	in the archive will be selected.  Any attempt
	   to append to	an archive in a	format different from the format
	   already used	in the archive will cause pax to exit immediately with
	   a non-zero exit status.  The	blocking size used in the archive vol-
	   ume where writing starts will continue to be	used for the remainder
	   of that archive volume.

	   Warning: Many storage devices are not able to support the opera-
	   tions necessary to perform an append	operation.  Any	attempt	to
	   append to an	archive	stored on such a device	may damage the archive
	   or have other unpredictable results.	 Tape drives in	particular are
	   more	likely to not support an append	operation.  An archive stored
	   in a	regular	file system file or on a disk device will usually sup-
	   port	an append operation.

     -b	blocksize
	   When	writing	an archive, block the output at	a positive decimal
	   integer number of bytes per write to	the archive file.  The
	   blocksize must be a multiple	of 512 bytes with a maximum of 64512
	   bytes.  A blocksize larger than 32256 bytes violates	the POSIX
	   standard and	will not be portable to	all systems.  A	blocksize can
	   end with k or b to specify multiplication by	1024 (1K) or 512,
	   respectively.  A pair of blocksizes can be separated	by x to	indi-
	   cate	a product.  A specific archive device may impose additional
	   restrictions	on the size of blocking	it will	support.  When block-
	   ing is not specified, the default blocksize is dependent on the
	   specific archive format being used (see the -x option).

     -c	   Match all file or archive members except those specified by the
	   pattern and file operands.

     -d	   Cause files of type directory being copied or archived, or archive
	   members of type directory being extracted, to match only the	direc-
	   tory	file or	archive	member and not the file	hierarchy rooted at
	   the directory.

     -f	archive
	   Specify archive as the pathname of the input	or output archive,
	   overriding the default standard input (for list and read) or
	   standard output (for	write).	 A single archive may span multiple
	   files and different archive devices.	 When required,	pax will
	   prompt for the pathname of the file or device of the	next volume in
	   the archive.

     -i	   Interactively rename	files or archive members.  For each archive
	   member matching a pattern operand or	each file matching a file op-
	   erand, pax will prompt to /dev/tty giving the name of the file, its
	   file	mode and its modification time.	 The pax utility will then
	   read	a line from /dev/tty.  If this line is blank, the file or ar-
	   chive member	is skipped.  If	this line consists of a	single period,
	   the file or archive member is processed with	no modification	to its
	   name.  Otherwise, its name is replaced with the contents of the
	   line.  The pax utility will immediately exit	with a non-zero	exit
	   status if <EOF> is encountered when reading a response or if
	   /dev/tty cannot be opened for reading and writing.

     -k	   Do not overwrite existing files.

     -l	   Link	files.	(The letter ell).  In the copy mode (-r	-w), hard
	   links are made between the source and destination file hierarchies
	   whenever possible.

     -n	   Select the first archive member that	matches	each pattern operand.
	   No more than	one archive member is matched for each pattern.	 When
	   members of type directory are matched, the file hierarchy rooted at
	   that	directory is also matched (unless -d is	also specified).

     -o	options
	   Information to modify the algorithm for extracting or writing ar-
	   chive files which is	specific to the	archive	format specified by
	   -x.	In general, options take the form: name=value

     -p	string
	   Specify one or more file characteristic options (privileges).  The
	   string option-argument is a string specifying file characteristics
	   to be retained or discarded on extraction.  The string consists of
	   the specification characters	a, e, m, o, and	p.  Multiple charac-
	   teristics can be concatenated within	the same string	and multiple
	   -p options can be specified.	 The meaning of	the specification
	   characters are as follows:

	   a   Do not preserve file access times.  By default, file access
	       times are preserved whenever possible.

	   e   `Preserve everything', the user ID, group ID, file mode bits,
	       file access time, and file modification time.  This is intended
	       to be used by root, someone with	all the	appropriate privi-
	       leges, in order to preserve all aspects of the files as they
	       are recorded in the archive.  The e flag	is the sum of the o
	       and p flags.

	   m   Do not preserve file modification times.	 By default, file mod-
	       ification times are preserved whenever possible.

	   o   Preserve	the user ID and	group ID.

	   p   `Preserve' the file mode	bits.  This intended to	be used	by a
	       user with regular privileges who	wants to preserve all aspects
	       of the file other than the ownership.  The file times are pre-
	       served by default, but two other	flags are offered to disable
	       this and	use the	time of	extraction instead.

	   In the preceding list, `preserve' indicates that an attribute
	   stored in the archive is given to the extracted file, subject to
	   the permissions of the invoking process.  Otherwise the attribute
	   of the extracted file is determined as part of the normal file cre-
	   ation action.  If neither the e nor the o specification character
	   is specified, or the	user ID	and group ID are not preserved for any
	   reason, pax will not	set the	S_ISUID	(setuid) and S_ISGID (setgid)
	   bits	of the file mode.  If the preservation of any of these items
	   fails for any reason, pax will write	a diagnostic message to
	   standard error.  Failure to preserve	these items will affect	the
	   final exit status, but will not cause the extracted file to be
	   deleted.  If	the file characteristic	letters	in any of the string
	   option-arguments are	duplicated or conflict with each other,	the
	   one(s) given	last will take precedence.  For	example, if
		 -p eme
	   is specified, file modification times are still preserved.

     -s	replstr
	   Modify the file or archive member names specified by	the pattern or
	   file	operands according to the substitution expression replstr,
	   using the syntax of the ed(1) utility regular expressions.  The
	   format of these regular expressions are:
		 /old/new/[gp]
	   As in ed(1),	old is a basic regular expression 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 com-
	   mand	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 for-
	   mat:
		 <original pathname> >>	<new pathname>
	   File	or archive member names	that substitute	to the empty string
	   are not selected and	will be	skipped.

     -t	   Reset the access times of any file or directory read	or accessed by
	   pax to be the same as they were before being	read or	accessed by
	   pax.

     -u	   Ignore files	that are older (having a less recent file modification
	   time) than a	pre-existing file or archive member with the same
	   name.  During read, an archive member with the same name as a file
	   in the file system will be extracted	if the archive member is newer
	   than	the file.  During write, a file	system member with the same
	   name	as an archive member will be written to	the archive if it is
	   newer than the archive member.  During copy,	the file in the	desti-
	   nation hierarchy is replaced	by the file in the source hierarchy or
	   by a	link to	the file in the	source hierarchy if the	file in	the
	   source hierarchy is newer.

     -v	   During a list operation, produce a verbose table of contents	using
	   the format of the ls(1) utility with	the -l option.	For pathnames
	   representing	a hard link to a previous member of the	archive, the
	   output has the format:
		 <ls -l	listing> == <link name>
	   For pathnames representing a	symbolic link, the output has the for-
	   mat:
		 <ls -l	listing> => <link name>
	   Where <ls -l	listing> is the	output format specified	by the ls(1)
	   utility when	used with the -l option.  Otherwise for	all the	other
	   operational modes (read, write, and copy), pathnames	are written
	   and flushed to standard error without a trailing <newline> as soon
	   as processing begins	on that	file or	archive	member.	 The trailing
	   <newline>, is not buffered, and is written only after the file has
	   been	read or	written.

     -x	format
	   Specify the output archive format, with the default format being
	   ustar.  The pax utility currently supports the following formats:

	   cpio	    The	extended cpio interchange format specified in the IEEE
		    Std	1003.2 (``POSIX.2'') standard.	The default blocksize
		    for	this format is 5120 bytes.  Inode and device informa-
		    tion about a file (used for	detecting file hard links by
		    this format) which may be truncated	by this	format is
		    detected by	pax and	is repaired.

	   bcpio    The	old binary cpio	format.	 The default blocksize for
		    this format	is 5120	bytes.	This format is not very	porta-
		    ble	and should not be used when other formats are avail-
		    able.  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 pax	and is
		    repaired.

	   sv4cpio  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 pax and is repaired.

	   sv4crc   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 by pax and is repaired.

	   tar	    The	old BSD	tar format as found in 4.3BSD.	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, a -o option can be used when writing an
		    archive to omit the	storage	of directories.	 This option
		    takes the form:
			  -o write_opt=nodir

	   ustar    The	extended tar interchange format	specified in the IEEE
		    Std	1003.2 (``POSIX.2'') standard.	The default blocksize
		    for	this format is 10240 bytes.  Pathnames stored by this
		    format must	be 255 characters or less in length.  The
		    directory part may be at most 155 characters and each path
		    component must be less than	100 characters.

	   The pax utility 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.

     -z	   Use gzip(1) to compress (decompress)	the archive while writing
	   (reading).  Incompatible with -a.

     -B	bytes
	   Limit the number of bytes written to	a single archive volume	to
	   bytes.  The bytes limit can end with	m, k, or b to specify multi-
	   plication by	1048576	(1M), 1024 (1K)	or 512,	respectively.  A pair
	   of bytes limits can be separated by x to indicate a product.

	   Warning: Only use this option when writing an archive to a device
	   which supports an end of file read condition	based on last (or
	   largest) write offset (such as a regular file or a tape drive).
	   The use of this option with a floppy	or hard	disk is	not recom-
	   mended.

     -D	   This	option is the same as the -u option, except that the file
	   inode change	time is	checked	instead	of the file modification time.
	   The file inode change time can be used to select files whose	inode
	   information (e.g. uid, gid, etc.) is	newer than a copy of the file
	   in the destination directory.

     -E	limit
	   Limit the number of consecutive read	faults while trying to read a
	   flawed archives to limit.  With a positive limit, pax will attempt
	   to recover from an archive read error and will continue processing
	   starting with the next file stored in the archive.  A limit of 0
	   will	cause pax to stop operation after the first read error is
	   detected on an archive volume.  A limit of NONE will	cause pax to
	   attempt to recover from read	errors forever.	 The default limit is
	   a small positive number of retries.

	   Warning: Using this option with NONE	should be used with extreme
	   caution as pax may get stuck	in an infinite loop on a very badly
	   flawed archive.

     -G	group
	   Select a file based on its group name, or when starting with	a #, a
	   numeric gid.	 A '\' can be used to escape the #.  Multiple -G
	   options may be supplied and checking	stops with the first match.

     -H	   Follow only command line symbolic links while performing a physical
	   file	system traversal.

     -L	   Follow all symbolic links to	perform	a logical file system traver-
	   sal.

     -P	   Do not follow symbolic links, perform a physical file system	tra-
	   versal.  This is the	default	mode.

     -T	[from_date][,to_date][/[c][m]]
	   Allow files to be selected based on a file modification or inode
	   change time falling within a	specified time range of	from_date to
	   to_date (the	dates are inclusive).  If only a from_date is sup-
	   plied, all files with a modification	or inode change	time equal to
	   or younger are selected.  If	only a to_date is supplied, all	files
	   with	a modification or inode	change time equal to or	older will be
	   selected.  When the from_date is equal to the to_date, only files
	   with	a modification or inode	change time of exactly that time will
	   be selected.

	   When	pax is in the write or copy mode, the optional trailing	field
	   [c][m] can be used to determine which file time (inode change, file
	   modification	or both) are used in the comparison.  If neither is
	   specified, the default is to	use file modification time only.  The
	   m specifies the comparison of file modification time	(the time when
	   the file was	last written).	The c specifies	the comparison of
	   inode change	time (the time when the	file inode was last changed;
	   e.g.	a change of owner, group, mode,	etc).  When c and m are	both
	   specified, then the modification and	inode change times are both
	   compared.  The inode	change time comparison is useful in selecting
	   files whose attributes were recently	changed	or selecting files
	   which were recently created and had their modification time reset
	   to an older time (as	what happens when a file is extracted from an
	   archive and the modification	time is	preserved).  Time comparisons
	   using both file times is useful when	pax is used to create a	time
	   based incremental archive (only files that were changed during a
	   specified time range	will be	archived).

	   A time range	is made	up of six different fields and each field must
	   contain two digits.	The format is:
		 [yy[mm[dd[hh]]]]mm[.ss]
	   Where yy is the last	two digits of the year,	the first mm is	the
	   month (from 01 to 12), dd is	the day	of the month (from 01 to 31),
	   hh is the hour of the day (from 00 to 23), the second mm is the
	   minute (from	00 to 59), and ss is the seconds (from 00 to 59).  The
	   minute field	mm is required,	while the other	fields are optional
	   and must be added in	the following order:
		 hh, dd, mm, yy.
	   The ss field	may be added independently of the other	fields.	 Time
	   ranges are relative to the current time, so
		 -T 1234/cm
	   would select	all files with a modification or inode change time of
	   12:34 PM today or later.  Multiple -T time range can	be supplied
	   and checking	stops with the first match.

     -U	user
	   Select a file based on its user name, or when starting with a #, a
	   numeric uid.	 A '\' can be used to escape the #.  Multiple -U
	   options may be supplied and checking	stops with the first match.

     -X	   When	traversing the file hierarchy specified	by a pathname, do not
	   descend into	directories that have a	different device ID.  See the
	   st_dev field	as described in	stat(2)	for more information about
	   device ID's.

     -Y	   This	option is the same as the -D option, except that the inode
	   change time is checked using	the pathname created after all the
	   file	name modifications have	completed.

     -Z	   This	option is the same as the -u option, except that the modifica-
	   tion	time is	checked	using the pathname created after all the file
	   name	modifications have completed.

     The options that operate on the names of files or archive members (-c,
     -i, -n, -s, -u, -v, -D, -G, -T, -U, -Y, and -Z) interact as follows.

     When extracting files during a read operation, archive members are
     `selected', based only on the user	specified pattern operands as modified
     by	the -c,	-n, -u,	-D, -G,	-T, -U options.	 Then any -s and -i options
     will modify in that order,	the names of these selected files.  Then the
     -Y	and -Z options will be applied based on	the final pathname.  Finally
     the -v option will	write the names	resulting from these modifications.

     When archiving files during a write operation, or copying files during a
     copy operation, archive members are `selected', based only	on the user
     specified pathnames as modified by	the -n,	-u, -D,	-G, -T,	and -U options
     (the -D option only applies during	a copy operation).  Then any -s	and -i
     options will modify in that order,	the names of these selected files.
     Then during a copy	operation the -Y and the -Z options will be applied
     based on the final	pathname.  Finally the -v option will write the	names
     resulting from these modifications.

     When one or both of the -u	or -D options are specified along with the -n
     option, a file is not considered selected unless it is newer than the
     file to which it is compared.

EXIT STATUS
     The pax utility will exit with one	of the following values:

     0	 All files were	processed successfully.

     1	 An error occurred.

EXAMPLES
     The command:
	   pax -w -f /dev/sa0 .
     copies the	contents of the	current	directory to the device	/dev/sa0.

     The command:
	   pax -v -f filename
     gives the verbose table of	contents for an	archive	stored in filename.

     The following commands:
	   mkdir /tmp/to
	   cd /tmp/from
	   pax -rw . /tmp/to
     will copy the entire /tmp/from directory hierarchy	to /tmp/to.

     The command:
	   pax -r -s ',^//*usr//*,,' -f	a.pax
     reads the archive a.pax, with all files rooted in ``/usr''	into the ar-
     chive extracted relative to the current directory.

     The command:
	   pax -rw -i .	dest_dir
     can be used to interactively select the files to copy from	the current
     directory to dest_dir.

     The command:
	   pax -r -pe -U root -G bin -f	a.pax
     will extract all files from the archive a.pax which are owned by root
     with group	bin and	will preserve all file permissions.

     The command:
	   pax -r -w -v	-Y -Z home /backup
     will update (and list) only those files in	the destination	directory
     /backup which are older (less recent inode	change or file modification
     times) than files with the	same name found	in the source file tree	home.

DIAGNOSTICS
     Whenever pax cannot create	a file or a link when reading an archive or
     cannot find a file	when writing an	archive, or cannot preserve the	user
     ID, group ID, or file mode	when the -p option is specified, a diagnostic
     message is	written	to standard error and a	non-zero exit status will be
     returned, but processing will continue.  In the case where	pax cannot
     create a link to a	file, pax 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,	pax may	have only partially extracted a	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, pax	may have only partially	created	the archive which may violate
     the specific archive format specification.

     If	while doing a copy, pax	detects	a file is about	to overwrite itself,
     the file is not copied, a diagnostic message is written to	standard error
     and when pax completes it will exit with a	non-zero exit status.

SEE ALSO
     cpio(1), tar(1)

STANDARDS
     The pax utility is	a superset of the IEEE Std 1003.2 (``POSIX.2'')	stan-
     dard.  The	options	-z, -B,	-D, -E,	-G, -H,	-L, -P,	-T, -U,	-Y, -Z,	the
     archive formats bcpio, sv4cpio, sv4crc, tar, and the flawed archive han-
     dling during list and read	operations are extensions to the POSIX stan-
     dard.

HISTORY
     The pax utility appeared in 4.4BSD.

AUTHORS
     Keith Muller at the University of California, San Diego

BUGS
     The pax utility does not recognize	multibyte characters.

FreeBSD	10.1			August 29, 2010			  FreeBSD 10.1

NAME | SYNOPSIS | DESCRIPTION | OPERANDS | OPTIONS | EXIT STATUS | EXAMPLES | DIAGNOSTICS | SEE ALSO | STANDARDS | HISTORY | AUTHORS | BUGS

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