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PAX(1)				   BSD General Commands Manual				   PAX(1)

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

SYNOPSIS
     pax [-0cdjnOVvz] [-E limit] [-f archive] [-N dbdir] [-s replstr] ... [-U user] ...
	 [-G group] ... [-T [from_date][,to_date]] ... [pattern ...]
     pax -r [-AcDdijknOuVvYZz] [-E limit] [-f archive] [-N dbdir] [-o options] ... [-p string]
	 ... [-s replstr] ... [-U user] ... [-G group] ... [-T [from_date][,to_date]] ...
	 [pattern ...]
     pax -w [-AdHijLMOPtuVvXz] [-b blocksize] [[-a] [-f archive]] [-x format] [-B bytes]
	 [-N dbdir] [-o options] ... [-s replstr] ... [-U user] ... [-G group] ... [-T
	 [from_date][,to_date][/[c][m]]] ... [file ...]
     pax -r -w [-ADdHijkLlMnOPtuVvXYZz] [-N dbdir] [-p string] ... [-s replstr] ... [-U user] ...
	 [-G group] ... [-T [from_date][,to_date][/[c][m]]] ... [file ...] directory

DESCRIPTION
     pax will read, write, and list the members of an archive file, and will copy directory hier-
     archies.  If the archive file is of the form: [[user@]host:]file then the archive will be
     processed using rmt(8).

     pax operation is independent of the specific archive format, and supports a wide variety of
     different 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 following functional modes
     pax will operate under: list, read, write, and copy.

     <none>  List.  pax will write to standard output a table of contents of the members of the
	     archive file read from standard input, whose pathnames match the specified patterns.
	     The table of contents contains one filename per line and is written using single
	     line buffering.

     -r      Read.  pax extracts 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.  pax writes 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.  pax copies the file operands to the destination directory.	When no file op-
	     erands 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 directory will be included.  The effect of the copy is as if the
	     copied files were written to an archive file and then subsequently 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 possible (see the -E option for more details on error han-
     dling).

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 notation 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 op-
     erand does not select at least one archive member, pax will write these file operand path-
     names 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 archive 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 op-
	   erands 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 for-
	   mat 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 volume 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 operations necessary to per-
	   form 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 support 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 32256 bytes.  A blocksize can end with k or b to specify multiplica-
	   tion by 1024 (1K) or 512, respectively.  A pair of blocksizes can be separated by x to
	   indicate a product.	A specific archive device may impose additional restrictions on
	   the size of blocking it will support.  When blocking 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 oper-
	   ands.

     -d    Cause files of type directory being copied or archived, or archive members of type
	   directory being extracted, to match only the directory 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 operand, pax will prompt to /dev/tty giv-
	   ing the name of the file, its file mode and its modification time.  pax will then read
	   a line from /dev/tty.  If this line is blank, the file or archive 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.  pax 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.

     -j    Use bzip2(1) for compression when reading or writing archive files.

     -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 archive 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-argu-
	   ment 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 characteristics 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 privileges, 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 modification times are
	       preserved whenever possible.

	   o   Preserve the user ID and group ID.

	   p   'Preserve' the file mode bits.  This is 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 preserved by default, but two other flags are offered to dis-
	       able 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.  Oth-
	   erwise the attribute of the extracted file is determined as part of the normal file
	   creation 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 let-
	   ters 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) util-
	   ity 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 delim-
	   iter (/ 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 substi-
	   tution expression to the pathname substring which starts with the first character fol-
	   lowing the end of the last successful substitution.	The first unsuccessful substitu-
	   tion 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 fol-
	   lowing format:
		 <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, if the user has the appropriate
	   permissions required by utime(3).

     -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 mem-
	   ber 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 mem-
	   ber.  During copy, the file in the destination 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 previ-
	   ous member of the archive, the output has the format:
		 <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 process-
	   ing 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.

	   A final summary of archive operations is printed after they have been completed.

     -x format
	   Specify the output archive format, with the default format being ustar.  pax 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 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.

	   bcpio    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 for-
		    mat is detected by pax and is repaired.

	   sv4cpio  The AT&T System V Release 4 UNIX 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 AT&T System V Release 4 UNIX 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 trun-
		    cated 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 charac-
		    ters or less in length.  Only regular files, hard links, soft links, and
		    directories will be archived (other file types are not supported).	For back-
		    ward 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 250 characters or less in
		    length.

	   pax 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.

     --xz  Use xz(1) compression, when reading or writing archive files.

     -z    Use gzip(1) compression, when reading or writing archive files.

     -A    Do not strip leading `/'s from file names.

     -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 multiplication by 1048576 (1M), 1024 (1K) or
	   512, respectively.  A pair of bytes limits can be separated by x to indicate a prod-
	   uct.

	   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 rec-
	   ommended.

     -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 tra-
	   versal.

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

     -M    During a write or copy operation, treat the list of files on standard input as an
	   mtree(8) 'specfile' specification, and write or copy only those items in the specfile.

	   If the file exists in the underlying file system, its permissions and modification
	   time will be used unless specifically overridden by the specfile.  An error will be
	   raised if the type of entry in the specfile conflicts with that of an existing file.
	   A directory entry that is marked 'optional' will not be copied (even though its con-
	   tents will be).

	   Otherwise, the entry will be 'faked-up', and it is necessary to specify at least the
	   following parameters in the specfile: type, mode, gname or gid, and uname or uid,
	   device (in the case of block or character devices), and link (in the case of symbolic
	   links).  If time isn't provided, the current time will be used.  A 'faked-up' entry
	   that is marked 'optional' will not be copied.

     -N dbdir
	   Except for lookups for the -G and -U options, use the user database text file
	   master.passwd and group database text file group from dbdir, rather than using the
	   results from the system's getpwnam(3) and getgrnam(3) (and related) library calls.

     -O    Force the archive to be one volume.	If a volume ends prematurely, pax will not prompt
	   for a new volume.  This option can be useful for automated tasks where error recovery
	   cannot be performed by a human.

     -P    Do not follow symbolic links, perform a physical file system traversal.  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 supplied, 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 modifica-
	   tion 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 com-
	   pared.  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 dig-
	   its.  The format is:
		 [[[[[cc]yy]mm]dd]hh]mm[.ss]
	   Where cc is the first two digits of the year (the century), 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 61).  Only the minute field
	   mm is required; the others will default to the current system values.  The ss field
	   may be added independently of the other fields.  If the century is not specified, it
	   defaults to 1900 for years between 69 and 99, or 2000 for years between 0 and 68.
	   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.

     -V    A final summary of archive operations is printed after they have been completed.  Some
	   potentially long-running tape operations are noted.

     -X    When traversing the file hierarchy specified by a pathname, do not descend into direc-
	   tories 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 modification time is checked
	   using the pathname created after all the file name modifications have completed.

     -0    Use the nul character instead of \n as the file separator when reading files from
	   standard input.

     --force-local
	   Do not interpret filenames that contain a `:' as remote files.

     --insecure
	   Normally pax ignores filenames that contain ``..'' as a path component.  With this
	   option, files that contain ``..'' can be processed.

     --use-compress-program
	   Use the named program as the program to decompress the input or compress the output.

     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, ar-
     chive 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
     pax will exit with one of the following values:

     0	 All files were processed successfully.

     1	 An error occurred.

     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 specifica-
     tion.

     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.

EXAMPLES
     The command:
	   pax -w -f /dev/rst0 .
     copies the contents of the current directory to the device /dev/rst0.

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

     The following commands:
	   mkdir newdir
	   cd olddir
	   pax -rw -pp . ../newdir
     will copy the entire olddir directory hierarchy to newdir, preserving permissions and access
     times.

     When running as root, one may also wish to preserve file ownership when copying directory
     trees.  This can be done with the following commands:
	   cd olddir
	   pax -rw -pe . ../newdir
     which will copy the contents of olddir into ../newdir, preserving ownership, permissions and
     access times.

     The command:
	   pax -r -s ',^//*usr//*,,' -f a.pax
     reads the archive a.pax, with all files rooted in ``/usr'' into the archive extracted rela-
     tive 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.

SEE ALSO
     cpio(1), tar(1), symlink(7), mtree(8)

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

AUTHORS
     Keith Muller at the University of California, San Diego.  Luke Mewburn implemented -M.

BSD					  June 18, 2011 				      BSD
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