xref: /netbsd-src/bin/pax/pax.1 (revision 567219e1d7461bff1b180e494a9674a287b057a7)
1.\"    $NetBSD: pax.1,v 1.61 2011/06/19 07:34:24 wiz Exp $
2.\"
3.\" Copyright (c) 1992 Keith Muller.
4.\" Copyright (c) 1992, 1993
5.\"	The Regents of the University of California.  All rights reserved.
6.\"
7.\" This code is derived from software contributed to Berkeley by
8.\" Keith Muller of the University of California, San Diego.
9.\"
10.\" Redistribution and use in source and binary forms, with or without
11.\" modification, are permitted provided that the following conditions
12.\" are met:
13.\" 1. Redistributions of source code must retain the above copyright
14.\"    notice, this list of conditions and the following disclaimer.
15.\" 2. Redistributions in binary form must reproduce the above copyright
16.\"    notice, this list of conditions and the following disclaimer in the
17.\"    documentation and/or other materials provided with the distribution.
18.\" 3. Neither the name of the University nor the names of its contributors
19.\"    may be used to endorse or promote products derived from this software
20.\"    without specific prior written permission.
21.\"
22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32.\" SUCH DAMAGE.
33.\"
34.\"	@(#)pax.1	8.4 (Berkeley) 4/18/94
35.\"
36.Dd June 18, 2011
37.Dt PAX 1
38.Os
39.Sh NAME
40.Nm pax
41.Nd read and write file archives and copy directory hierarchies
42.Sh SYNOPSIS
43.Nm
44.Op Fl 0cdjnOVvz
45.Op Fl E Ar limit
46.Op Fl f Ar archive
47.Op Fl N Ar dbdir
48.Op Fl s Ar replstr
49.Ar ...\&
50.Op Fl U Ar user
51.Ar ...\&
52.Op Fl G Ar group
53.Ar ...\&
54.Oo
55.Fl T
56.Sm off
57.Op Ar from_date
58.Oo , Ar to_date Oc
59.Sm on
60.Oc
61.Ar ...\&
62.Op Ar pattern ...\&
63.Nm
64.Fl r
65.Op Fl AcDdijknOuVvYZz
66.Op Fl E Ar limit
67.Op Fl f Ar archive
68.Op Fl N Ar dbdir
69.Op Fl o Ar options
70.Ar ...\&
71.Op Fl p Ar string
72.Ar ...\&
73.Op Fl s Ar replstr
74.Ar ...\&
75.Op Fl U Ar user
76.Ar ...\&
77.Op Fl G Ar group
78.Ar ...\&
79.Oo
80.Fl T
81.Sm off
82.Op Ar from_date
83.Oo , Ar to_date Oc
84.Sm on
85.Oc
86.Ar ...\&
87.Op Ar pattern ...\&
88.Nm
89.Fl w
90.Op Fl AdHijLMOPtuVvXz
91.Op Fl b Ar blocksize
92.Oo
93.Op Fl a
94.Op Fl f Ar archive
95.Oc
96.Op Fl x Ar format
97.Op Fl B Ar bytes
98.Op Fl N Ar dbdir
99.Op Fl o Ar options
100.Ar ...\&
101.Op Fl s Ar replstr
102.Ar ...\&
103.Op Fl U Ar user
104.Ar ...\&
105.Op Fl G Ar group
106.Ar ...\&
107.Oo
108.Fl T
109.Sm off
110.Op Ar from_date
111.Oo , Ar to_date Oc
112.Oo /[ Cm c ] [ Cm m ] Oc
113.Sm on
114.Oc
115.Ar ...\&
116.Op Ar file ...\&
117.Nm
118.Fl r
119.Fl w
120.Op Fl ADdHijkLlMnOPtuVvXYZz
121.Op Fl N Ar dbdir
122.Op Fl p Ar string
123.Ar ...\&
124.Op Fl s Ar replstr
125.Ar ...\&
126.Op Fl U Ar user
127.Ar ...\&
128.Op Fl G Ar group
129.Ar ...\&
130.Oo
131.Fl T
132.Sm off
133.Op Ar from_date
134.Oo , Ar to_date Oc
135.Oo /[ Cm c ] [ Cm m ] Oc
136.Sm on
137.Oc
138.Ar ...\&
139.Op Ar file ...\&
140.Ar directory
141.Sh DESCRIPTION
142.Nm
143will read, write, and list the members of an archive file,
144and will copy directory hierarchies.
145If the archive file is of the form:
146.Ar [[user@]host:]file
147then the archive will be processed using
148.Xr rmt 8 .
149.Pp
150.Nm
151operation is independent of the specific archive format,
152and supports a wide variety of different archive formats.
153A list of supported archive formats can be found under the description of the
154.Fl x
155option.
156.Pp
157The presence of the
158.Fl r
159and the
160.Fl w
161options specifies which of the following functional modes
162.Nm
163will operate under:
164.Em list , read , write ,
165and
166.Em copy .
167.Bl -tag -width 6n
168.It Aq none
169.Em List .
170.Nm
171will write to
172.Dv standard output
173a table of contents of the members of the archive file read from
174.Dv standard input ,
175whose pathnames match the specified
176.Ar patterns .
177The table of contents contains one filename per line
178and is written using single line buffering.
179.It Fl r
180.Em Read .
181.Nm
182extracts the members of the archive file read from the
183.Dv standard input ,
184with pathnames matching the specified
185.Ar patterns .
186The archive format and blocking is automatically determined on input.
187When an extracted file is a directory, the entire file hierarchy
188rooted at that directory is extracted.
189All extracted files are created relative to the current file hierarchy.
190The setting of ownership, access and modification times, and file mode of
191the extracted files are discussed in more detail under the
192.Fl p
193option.
194.It Fl w
195.Em Write .
196.Nm
197writes an archive containing the
198.Ar file
199operands to
200.Dv standard output
201using the specified archive format.
202When no
203.Ar file
204operands are specified, a list of files to copy with one per line is read from
205.Dv standard input .
206When a
207.Ar file
208operand is also a directory, the entire file hierarchy rooted
209at that directory will be included.
210.It Fl r Fl w
211.Em Copy .
212.Nm
213copies the
214.Ar file
215operands to the destination
216.Ar directory .
217When no
218.Ar file
219operands are specified, a list of files to copy with one per line is read from
220the
221.Dv standard input .
222When a
223.Ar file
224operand is also a directory the entire file
225hierarchy rooted at that directory will be included.
226The effect of the
227.Em copy
228is as if the copied files were written to an archive file and then
229subsequently extracted, except that there may be hard links between
230the original and the copied files (see the
231.Fl l
232option below).
233.Pp
234.Em Warning :
235The destination
236.Ar directory
237must not be one of the
238.Ar file
239operands or a member of a file hierarchy rooted at one of the
240.Ar file
241operands.
242The result of a
243.Em copy
244under these conditions is unpredictable.
245.El
246.Pp
247While processing a damaged archive during a
248.Em read
249or
250.Em list
251operation,
252.Nm
253will attempt to recover from media defects and will search through the archive
254to locate and process the largest number of archive members possible (see the
255.Fl E
256option for more details on error handling).
257.Sh OPERANDS
258The
259.Ar directory
260operand specifies a destination directory pathname.
261If the
262.Ar directory
263operand does not exist, or it is not writable by the user,
264or it is not of type directory,
265.Nm
266will exit with a non-zero exit status.
267.Pp
268The
269.Ar pattern
270operand is used to select one or more pathnames of archive members.
271Archive members are selected using the pattern matching notation described
272by
273.Xr fnmatch 3 .
274When the
275.Ar pattern
276operand is not supplied, all members of the archive will be selected.
277When a
278.Ar pattern
279matches a directory, the entire file hierarchy rooted at that directory will
280be selected.
281When a
282.Ar pattern
283operand does not select at least one archive member,
284.Nm
285will write these
286.Ar pattern
287operands in a diagnostic message to
288.Dv standard error
289and then exit with a non-zero exit status.
290.Pp
291The
292.Ar file
293operand specifies the pathname of a file to be copied or archived.
294When a
295.Ar file
296operand does not select at least one archive member,
297.Nm
298will write these
299.Ar file
300operand pathnames in a diagnostic message to
301.Dv standard error
302and then exit with a non-zero exit status.
303.Sh OPTIONS
304The following options are supported:
305.Bl -tag -width 4n
306.It Fl r
307Read an archive file from
308.Dv standard input
309and extract the specified
310.Ar files .
311If any intermediate directories are needed in order to extract an archive
312member, these directories will be created as if
313.Xr mkdir 2
314was called with the bitwise inclusive
315.Dv OR
316of
317.Dv S_IRWXU , S_IRWXG ,
318and
319.Dv S_IRWXO
320as the mode argument.
321When the selected archive format supports the specification of linked
322files and these files cannot be linked while the archive is being extracted,
323.Nm
324will write a diagnostic message to
325.Dv standard error
326and exit with a non-zero exit status at the completion of operation.
327.It Fl w
328Write files to the
329.Dv standard output
330in the specified archive format.
331When no
332.Ar file
333operands are specified,
334.Dv standard input
335is read for a list of pathnames with one per line without any leading or
336trailing
337.Aq blanks .
338.It Fl a
339Append
340.Ar files
341to the end of an archive that was previously written.
342If an archive format is not specified with a
343.Fl x
344option, the format currently being used in the archive will be selected.
345Any attempt to append to an archive in a format different from the
346format already used in the archive will cause
347.Nm
348to exit immediately
349with a non-zero exit status.
350The blocking size used in the archive volume where writing starts
351will continue to be used for the remainder of that archive volume.
352.Pp
353.Em Warning :
354Many storage devices are not able to support the operations necessary
355to perform an append operation.
356Any attempt to append to an archive stored on such a device may damage the
357archive or have other unpredictable results.
358Tape drives in particular are more likely to not support an append operation.
359An archive stored in a regular file system file or on a disk device will
360usually support an append operation.
361.It Fl b Ar blocksize
362When
363.Em writing
364an archive,
365block the output at a positive decimal integer number of
366bytes per write to the archive file.
367The
368.Ar blocksize
369must be a multiple of 512 bytes with a maximum of 32256 bytes.
370A
371.Ar blocksize
372can end with
373.Li k
374or
375.Li b
376to specify multiplication by 1024 (1K) or 512, respectively.
377A pair of
378.Ar blocksizes
379can be separated by
380.Li x
381to indicate a product.
382A specific archive device may impose additional restrictions on the size
383of blocking it will support.
384When blocking is not specified, the default
385.Ar blocksize
386is dependent on the specific archive format being used (see the
387.Fl x
388option).
389.It Fl c
390Match all file or archive members
391.Em except
392those specified by the
393.Ar pattern
394and
395.Ar file
396operands.
397.It Fl d
398Cause files of type directory being copied or archived, or archive members of
399type directory being extracted, to match only the directory file or archive
400member and not the file hierarchy rooted at the directory.
401.It Fl f Ar archive
402Specify
403.Ar archive
404as the pathname of the input or output archive, overriding the default
405.Dv standard input
406(for
407.Em list
408and
409.Em read )
410or
411.Dv standard output
412(for
413.Em write ) .
414A single archive may span multiple files and different archive devices.
415When required,
416.Nm
417will prompt for the pathname of the file or device of the next volume in the
418archive.
419.It Fl i
420Interactively rename files or archive members.
421For each archive member matching a
422.Ar pattern
423operand or each file matching a
424.Ar file
425operand,
426.Nm
427will prompt to
428.Pa /dev/tty
429giving the name of the file, its file mode and its modification time.
430.Nm
431will then read a line from
432.Pa /dev/tty .
433If this line is blank, the file or archive member is skipped.
434If this line consists of a single period, the
435file or archive member is processed with no modification to its name.
436Otherwise, its name is replaced with the contents of the line.
437.Nm
438will immediately exit with a non-zero exit status if
439.Aq Dv EOF
440is encountered when reading a response or if
441.Pa /dev/tty
442cannot be opened for reading and writing.
443.It Fl j
444Use
445.Xr bzip2 1
446for compression when reading or writing archive files.
447.It Fl k
448Do not overwrite existing files.
449.It Fl l
450Link files.
451(The letter ell).
452In the
453.Em copy
454mode
455.Fl ( r
456.Fl w ) ,
457hard links are made between the source and destination file hierarchies
458whenever possible.
459.It Fl n
460Select the first archive member that matches each
461.Ar pattern
462operand.
463No more than one archive member is matched for each
464.Ar pattern .
465When members of type directory are matched, the file hierarchy rooted at that
466directory is also matched (unless
467.Fl d
468is also specified).
469.It Fl o Ar options
470Information to modify the algorithm for extracting or writing archive files
471which is specific to the archive format specified by
472.Fl x .
473In general,
474.Ar options
475take the form:
476.Cm name=value
477.It Fl p Ar string
478Specify one or more file characteristic options (privileges).
479The
480.Ar string
481option-argument is a string specifying file characteristics to be retained or
482discarded on extraction.
483The string consists of the specification characters
484.Cm a , e ,
485.Cm m , o ,
486and
487.Cm p .
488Multiple characteristics can be concatenated within the same string
489and multiple
490.Fl p
491options can be specified.
492The meaning of the specification characters are as follows:
493.Bl -tag -width 2n
494.It Cm a
495Do not preserve file access times.
496By default, file access times are preserved whenever possible.
497.It Cm e
498.Sq Preserve everything ,
499the user ID, group ID, file mode bits,
500file access time, and file modification time.
501This is intended to be used by
502.Em root ,
503someone with all the appropriate privileges, in order to preserve all
504aspects of the files as they are recorded in the archive.
505The
506.Cm e
507flag is the sum of the
508.Cm o
509and
510.Cm p
511flags.
512.\" .It Cm f
513.\" Do not preserve file flags.
514.\" By default, file flags are preserved whenever possible.
515.It Cm m
516Do not preserve file modification times.
517By default, file modification times are preserved whenever possible.
518.It Cm o
519Preserve the user ID and group ID.
520.It Cm p
521.Sq Preserve
522the file mode bits.
523This is intended to be used by a
524.Em user
525with regular privileges who wants to preserve all aspects of the file other
526than the ownership.
527The file times are preserved by default, but two other flags are offered to
528disable this and use the time of extraction instead.
529.El
530.Pp
531In the preceding list,
532.Sq preserve
533indicates that an attribute stored in the archive is given to the
534extracted file, subject to the permissions of the invoking
535process.
536Otherwise the attribute of the extracted file is determined as
537part of the normal file creation action.
538If neither the
539.Cm e
540nor the
541.Cm o
542specification character is specified, or the user ID and group ID are not
543preserved for any reason,
544.Nm
545will not set the
546.Dv S_ISUID
547.Em ( setuid )
548and
549.Dv S_ISGID
550.Em ( setgid )
551bits of the file mode.
552If the preservation of any of these items fails for any reason,
553.Nm
554will write a diagnostic message to
555.Dv standard error .
556Failure to preserve these items will affect the final exit status,
557but will not cause the extracted file to be deleted.
558If the file characteristic letters in any of the string option-arguments are
559duplicated or conflict with each other, the one(s) given last will take
560precedence.
561For example, if
562.Dl Fl p Ar eme
563is specified, file modification times are still preserved.
564.It Fl s Ar replstr
565Modify the file or archive member names specified by the
566.Ar pattern
567or
568.Ar file
569operands according to the substitution expression
570.Ar replstr ,
571using the syntax of the
572.Xr ed 1
573utility regular expressions.
574The format of these regular expressions are:
575.Dl /old/new/[gp]
576As in
577.Xr ed 1 ,
578.Cm old
579is a basic regular expression and
580.Cm new
581can contain an ampersand (\*[Am]), \en (where n is a digit) back-references,
582or subexpression matching.
583The
584.Cm old
585string may also contain
586.Aq Dv newline
587characters.
588Any non-null character can be used as a delimiter (/ is shown here).
589Multiple
590.Fl s
591expressions can be specified.
592The expressions are applied in the order they are specified on the
593command line, terminating with the first successful substitution.
594The optional trailing
595.Cm g
596continues to apply the substitution expression to the pathname substring
597which starts with the first character following the end of the last successful
598substitution.
599The first unsuccessful substitution stops the operation of the
600.Cm g
601option.
602The optional trailing
603.Cm p
604will cause the final result of a successful substitution to be written to
605.Dv standard error
606in the following format:
607.Dl Ao "original pathname" Ac \*[Gt]\*[Gt] Ao "new pathname" Ac
608File or archive member names that substitute to the empty string
609are not selected and will be skipped.
610.It Fl t
611Reset the access times of any file or directory read or accessed by
612.Nm
613to be the same as they were before being read or accessed by
614.Nm ,
615if the user has the appropriate permissions required by
616.Xr utime 3 .
617.It Fl u
618Ignore files that are older (having a less recent file modification time)
619than a pre-existing file or archive member with the same name.
620During
621.Em read ,
622an archive member with the same name as a file in the file system will be
623extracted if the archive member is newer than the file.
624During
625.Em write ,
626a file system member with the same name as an archive member will be
627written to the archive if it is newer than the archive member.
628During
629.Em copy ,
630the file in the destination hierarchy is replaced by the file in the source
631hierarchy or by a link to the file in the source hierarchy if the file in
632the source hierarchy is newer.
633.It Fl v
634During a
635.Em list
636operation, produce a verbose table of contents using the format of the
637.Xr ls 1
638utility with the
639.Fl l
640option.
641For pathnames representing a hard link to a previous member of the archive,
642the output has the format:
643.Dl Ao "ls -l listing" Ac == Ao "link name" Ac
644Where
645.Aq "ls -l listing"
646is the output format specified by the
647.Xr ls 1
648utility when used with the
649.Fl l
650option.
651.Pp
652Otherwise for all the other operational modes
653.Em ( read , write ,
654and
655.Em copy ) ,
656pathnames are written and flushed to
657.Dv standard error
658without a trailing
659.Aq Dv newline
660as soon as processing begins on that file or
661archive member.
662The trailing
663.Aq Dv newline ,
664is not buffered, and is written only after the file has been read or written.
665.Pp
666A final summary of archive operations is printed after they have been
667completed.
668.It Fl x Ar format
669Specify the output archive format, with the default format being
670.Ar ustar .
671.Nm
672currently supports the following formats:
673.Bl -tag -width "sv4cpio"
674.It Ar cpio
675The extended cpio interchange format specified in the
676.St -p1003.2
677standard.
678The default blocksize for this format is 5120 bytes.
679Inode and device information about a file (used for detecting file hard links
680by this format) which may be truncated by this format is detected by
681.Nm
682and is repaired.
683.It Ar bcpio
684The old binary cpio format.
685The default blocksize for this format is 5120 bytes.
686This format is not very portable and should not be used when other formats
687are available.
688Inode and device information about a file (used for detecting file hard links
689by this format) which may be truncated by this format is detected by
690.Nm
691and is repaired.
692.It Ar sv4cpio
693The
694.At V.4
695cpio.
696The default blocksize for this format is 5120 bytes.
697Inode and device information about a file (used for detecting file hard links
698by this format) which may be truncated by this format is detected by
699.Nm
700and is repaired.
701.It Ar sv4crc
702The
703.At V.4
704cpio with file crc checksums.
705The default blocksize for this format is 5120 bytes.
706Inode and device information about a file (used for detecting file hard links
707by this format) which may be truncated by this format is detected by
708.Nm
709and is repaired.
710.It Ar tar
711The old
712.Bx
713tar format as found in
714.Bx 4.3 .
715The default blocksize for this format is 10240 bytes.
716Pathnames stored by this format must be 100 characters or less in length.
717Only
718.Em regular
719files,
720.Em  hard links , soft links ,
721and
722.Em  directories
723will be archived (other file types are not supported).
724For backward compatibility with even older tar formats, a
725.Fl o
726option can be used when writing an archive to omit the storage of directories.
727This option takes the form:
728.Dl Fl o Cm write_opt=nodir
729.It Ar ustar
730The extended tar interchange format specified in the
731.St -p1003.2
732standard.
733The default blocksize for this format is 10240 bytes.
734Pathnames stored by this format must be 250 characters or less in length.
735.El
736.Pp
737.Nm
738will detect and report any file that it is unable to store or extract
739as the result of any specific archive format restrictions.
740The individual archive formats may impose additional restrictions on use.
741Typical archive format restrictions include (but are not limited to):
742file pathname length, file size, link pathname length and the type of the file.
743.It Fl Fl xz
744Use
745.Xr xz 1
746compression, when reading or writing archive files.
747.It Fl z
748Use
749.Xr gzip 1
750compression, when reading or writing archive files.
751.It Fl A
752Do not strip leading `/'s from file names.
753.It Fl B Ar bytes
754Limit the number of bytes written to a single archive volume to
755.Ar bytes .
756The
757.Ar bytes
758limit can end with
759.Li m ,
760.Li k ,
761or
762.Li b
763to specify multiplication by 1048576 (1M), 1024 (1K) or 512, respectively.
764A pair of
765.Ar bytes
766limits can be separated by
767.Li x
768to indicate a product.
769.Pp
770.Em Warning :
771Only use this option when writing an archive to a device which supports
772an end of file read condition based on last (or largest) write offset
773(such as a regular file or a tape drive).
774The use of this option with a floppy or hard disk is not recommended.
775.It Fl D
776This option is the same as the
777.Fl u
778option, except that the file inode change time is checked instead of the
779file modification time.
780The file inode change time can be used to select files whose inode information
781(e.g. uid, gid, etc.) is newer than a copy of the file in the destination
782.Ar directory .
783.It Fl E Ar limit
784Limit the number of consecutive read faults while trying to read a flawed
785archives to
786.Ar limit .
787With a positive
788.Ar limit ,
789.Nm
790will attempt to recover from an archive read error and will
791continue processing starting with the next file stored in the archive.
792A
793.Ar limit
794of 0 will cause
795.Nm
796to stop operation after the first read error is detected on an archive volume.
797A
798.Ar limit
799of
800.Li NONE
801will cause
802.Nm
803to attempt to recover from read errors forever.
804The default
805.Ar limit
806is a small positive number of retries.
807.Pp
808.Em Warning :
809Using this option with
810.Li NONE
811should be used with extreme caution as
812.Nm
813may get stuck in an infinite loop on a very badly flawed archive.
814.It Fl G Ar group
815Select a file based on its
816.Ar group
817name, or when starting with a
818.Cm # ,
819a numeric gid.
820A '\e' can be used to escape the
821.Cm # .
822Multiple
823.Fl G
824options may be supplied and checking stops with the first match.
825.It Fl H
826Follow only command line symbolic links while performing a physical file
827system traversal.
828.It Fl L
829Follow all symbolic links to perform a logical file system traversal.
830.It Fl M
831During a
832.Em write
833or
834.Em copy
835operation, treat the list of files on
836.Dv standard input
837as an
838.Xr mtree 8
839.Sq specfile
840specification, and write or copy only those items in the specfile.
841.Pp
842If the file exists in the underlying file system, its permissions and
843modification time will be used unless specifically overridden by the specfile.
844An error will be raised if the type of entry in the specfile conflicts
845with that of an existing file.
846A directory entry that is marked
847.Sq Sy optional
848will not be copied (even though its contents will be).
849.Pp
850Otherwise, the entry will be
851.Sq faked-up ,
852and it is necessary to specify at least the following parameters
853in the specfile:
854.Sy type ,
855.Sy mode ,
856.Sy gname
857or
858.Sy gid ,
859and
860.Sy uname
861or
862.Sy uid ,
863.Sy device
864(in the case of block or character devices), and
865.Sy link
866(in the case of symbolic links).
867If
868.Sy time
869isn't provided, the current time will be used.
870A
871.Sq faked-up
872entry that is marked
873.Sq Sy optional
874will not be copied.
875.It Fl N Ar dbdir
876Except for lookups for the
877.Fl G
878and
879.Fl U
880options,
881use the user database text file
882.Pa master.passwd
883and group database text file
884.Pa group
885from
886.Ar dbdir ,
887rather than using the results from the system's
888.Xr getpwnam 3
889and
890.Xr getgrnam 3
891(and related) library calls.
892.It Fl O
893Force the archive to be one volume.
894If a volume ends prematurely,
895.Nm
896will not prompt for a new volume.
897This option can be useful for
898automated tasks where error recovery cannot be performed by a human.
899.It Fl P
900Do not follow symbolic links, perform a physical file system traversal.
901This is the default mode.
902.It Fl T Ar [from_date][,to_date][/[c][m]]
903Allow files to be selected based on a file modification or inode change
904time falling within a specified time range of
905.Ar from_date
906to
907.Ar to_date
908(the dates are inclusive).
909If only a
910.Ar from_date
911is supplied, all files with a modification or inode change time
912equal to or younger are selected.
913If only a
914.Ar to_date
915is supplied, all files with a modification or inode change time
916equal to or older will be selected.
917When the
918.Ar from_date
919is equal to the
920.Ar to_date ,
921only files with a modification or inode change time of exactly that
922time will be selected.
923.Pp
924When
925.Nm
926is in the
927.Em write
928or
929.Em copy
930mode, the optional trailing field
931.Ar [c][m]
932can be used to determine which file time (inode change, file modification or
933both) are used in the comparison.
934If neither is specified, the default is to use file modification time only.
935The
936.Ar m
937specifies the comparison of file modification time (the time when
938the file was last written).
939The
940.Ar c
941specifies the comparison of inode change time (the time when the file
942inode was last changed; e.g. a change of owner, group, mode, etc).
943When
944.Ar c
945and
946.Ar m
947are both specified, then the modification and inode change times are
948both compared.
949The inode change time comparison is useful in selecting files whose
950attributes were recently changed or selecting files which were recently
951created and had their modification time reset to an older time (as what
952happens when a file is extracted from an archive and the modification time
953is preserved).
954Time comparisons using both file times is useful when
955.Nm
956is used to create a time based incremental archive (only files that were
957changed during a specified time range will be archived).
958.Pp
959A time range is made up of six different fields and each field must contain two
960digits.
961The format is:
962.Dl [[[[[cc]yy]mm]dd]hh]mm[\&.ss]
963Where
964.Cm cc
965is the first two digits of the year (the century),
966.Cm yy
967is the last two digits of the year,
968the first
969.Cm mm
970is the month (from 01 to 12),
971.Cm dd
972is the day of the month (from 01 to 31),
973.Cm hh
974is the hour of the day (from 00 to 23),
975the second
976.Cm mm
977is the minute (from 00 to 59),
978and
979.Cm ss
980is the seconds (from 00 to 61).
981Only the minute field
982.Cm mm
983is required; the others will default to the current system values.
984The
985.Cm ss
986field may be added independently of the other fields.
987If the century is not specified, it defaults to 1900 for
988years between 69 and 99, or 2000 for years between 0 and 68.
989Time ranges are relative to the current time, so
990.Dl Fl T Ar 1234/cm
991would select all files with a modification or inode change time
992of 12:34 PM today or later.
993Multiple
994.Fl T
995time range can be supplied and checking stops with the first match.
996.It Fl U Ar user
997Select a file based on its
998.Ar user
999name, or when starting with a
1000.Cm # ,
1001a numeric uid.
1002A '\e' can be used to escape the
1003.Cm # .
1004Multiple
1005.Fl U
1006options may be supplied and checking stops with the first match.
1007.It Fl V
1008A final summary of archive operations is printed after they have been
1009completed.
1010Some potentially long-running tape operations are noted.
1011.It Fl X
1012When traversing the file hierarchy specified by a pathname,
1013do not descend into directories that have a different device ID.
1014See the
1015.Li st_dev
1016field as described in
1017.Xr stat 2
1018for more information about device ID's.
1019.It Fl Y
1020This option is the same as the
1021.Fl D
1022option, except that the inode change time is checked using the
1023pathname created after all the file name modifications have completed.
1024.It Fl Z
1025This option is the same as the
1026.Fl u
1027option, except that the modification time is checked using the
1028pathname created after all the file name modifications have completed.
1029.It Fl 0
1030Use the nul character instead of \en as the file separator when reading
1031files from standard input.
1032.It Fl Fl force-local
1033Do not interpret filenames that contain a `:' as remote files.
1034.It Fl Fl insecure
1035Normally
1036.Nm
1037ignores filenames that contain
1038.Dq ..
1039as a path component.
1040With this option,
1041files that contain
1042.Dq ..
1043can be processed.
1044.It Fl Fl use-compress-program
1045Use the named program as the program to decompress the input or compress
1046the output.
1047.El
1048.Pp
1049The options that operate on the names of files or archive members
1050.Fl ( c ,
1051.Fl i ,
1052.Fl n ,
1053.Fl s ,
1054.Fl u ,
1055.Fl v ,
1056.Fl D ,
1057.Fl G ,
1058.Fl T ,
1059.Fl U ,
1060.Fl Y ,
1061and
1062.Fl Z )
1063interact as follows.
1064.Pp
1065When extracting files during a
1066.Em read
1067operation, archive members are
1068.Sq selected ,
1069based only on the user specified pattern operands as modified by the
1070.Fl c ,
1071.Fl n ,
1072.Fl u ,
1073.Fl D ,
1074.Fl G ,
1075.Fl T ,
1076.Fl U
1077options.
1078Then any
1079.Fl s
1080and
1081.Fl i
1082options will modify in that order, the names of these selected files.
1083Then the
1084.Fl Y
1085and
1086.Fl Z
1087options will be applied based on the final pathname.
1088Finally the
1089.Fl v
1090option will write the names resulting from these modifications.
1091.Pp
1092When archiving files during a
1093.Em write
1094operation, or copying files during a
1095.Em copy
1096operation, archive members are
1097.Sq selected ,
1098based only on the user specified pathnames as modified by the
1099.Fl n ,
1100.Fl u ,
1101.Fl D ,
1102.Fl G ,
1103.Fl T ,
1104and
1105.Fl U
1106options (the
1107.Fl D
1108option only applies during a copy operation).
1109Then any
1110.Fl s
1111and
1112.Fl i
1113options will modify in that order, the names of these selected files.
1114Then during a
1115.Em copy
1116operation the
1117.Fl Y
1118and the
1119.Fl Z
1120options will be applied based on the final pathname.
1121Finally the
1122.Fl v
1123option will write the names resulting from these modifications.
1124.Pp
1125When one or both of the
1126.Fl u
1127or
1128.Fl D
1129options are specified along with the
1130.Fl n
1131option, a file is not considered selected unless it is newer
1132than the file to which it is compared.
1133.Sh EXIT STATUS
1134.Nm
1135will exit with one of the following values:
1136.Bl -tag -width 2n
1137.It 0
1138All files were processed successfully.
1139.It 1
1140An error occurred.
1141.El
1142.Pp
1143Whenever
1144.Nm
1145cannot create a file or a link when reading an archive or cannot
1146find a file when writing an archive, or cannot preserve the user ID,
1147group ID, or file mode when the
1148.Fl p
1149option is specified, a diagnostic message is written to
1150.Dv standard error
1151and a non-zero exit status will be returned, but processing will continue.
1152In the case where pax cannot create a link to a file,
1153.Nm
1154will not create a second copy of the file.
1155.Pp
1156If the extraction of a file from an archive is prematurely terminated by
1157a signal or error,
1158.Nm
1159may have only partially extracted a file the user wanted.
1160Additionally, the file modes of extracted files and directories
1161may have incorrect file bits, and the modification and access times may be
1162wrong.
1163.Pp
1164If the creation of an archive is prematurely terminated by a signal or error,
1165.Nm
1166may have only partially created the archive which may violate the specific
1167archive format specification.
1168.Pp
1169If while doing a
1170.Em copy ,
1171.Nm
1172detects a file is about to overwrite itself, the file is not copied,
1173a diagnostic message is written to
1174.Dv standard error
1175and when
1176.Nm
1177completes it will exit with a non-zero exit status.
1178.Sh EXAMPLES
1179The command:
1180.Dl pax -w -f /dev/rst0 \&.
1181copies the contents of the current directory to the device
1182.Pa /dev/rst0 .
1183.Pp
1184The command:
1185.Dl pax -v -f filename
1186gives the verbose table of contents for an archive stored in
1187.Pa filename .
1188.Pp
1189The following commands:
1190.Dl mkdir newdir
1191.Dl cd olddir
1192.Dl pax -rw -pp .\ ../newdir
1193will copy the entire
1194.Pa olddir
1195directory hierarchy to
1196.Pa newdir ,
1197preserving permissions and access times.
1198.Pp
1199When running as root, one may also wish to preserve file
1200ownership when copying directory trees.
1201This can be done with the following commands:
1202.Dl cd olddir
1203.Dl pax -rw -pe .\ ../newdir
1204which will copy the contents of
1205.Pa olddir
1206into
1207.Pa ../newdir ,
1208preserving ownership, permissions and access times.
1209.Pp
1210The command:
1211.Dl pax -r -s ',^//*usr//*,,' -f a.pax
1212reads the archive
1213.Pa a.pax ,
1214with all files rooted in ``/usr'' into the archive extracted relative to the
1215current directory.
1216.Pp
1217The command:
1218.Dl pax -rw -i .\ dest_dir
1219can be used to interactively select the files to copy from the current
1220directory to
1221.Pa dest_dir .
1222.Pp
1223The command:
1224.Dl pax -r -pe -U root -G bin -f a.pax
1225will extract all files from the archive
1226.Pa a.pax
1227which are owned by
1228.Em root
1229with group
1230.Em bin
1231and will preserve all file permissions.
1232.Pp
1233The command:
1234.Dl pax -r -w -v -Y -Z home /backup
1235will update (and list) only those files in the destination directory
1236.Pa /backup
1237which are older (less recent inode change or file modification times) than
1238files with the same name found in the source file tree
1239.Pa home .
1240.Sh SEE ALSO
1241.Xr cpio 1 ,
1242.Xr tar 1 ,
1243.Xr symlink 7 ,
1244.Xr mtree 8
1245.Sh STANDARDS
1246The
1247.Nm
1248utility is a superset of the
1249.St -p1003.2
1250standard.
1251The options
1252.Fl B ,
1253.Fl D ,
1254.Fl E ,
1255.Fl G ,
1256.Fl H ,
1257.Fl L ,
1258.Fl M ,
1259.Fl O ,
1260.Fl P ,
1261.Fl T ,
1262.Fl U ,
1263.Fl Y ,
1264.Fl Z ,
1265.Fl z ,
1266the archive formats
1267.Ar bcpio ,
1268.Ar sv4cpio ,
1269.Ar sv4crc ,
1270.Ar tar ,
1271and the flawed archive handling during
1272.Ar list
1273and
1274.Ar read
1275operations are extensions to the
1276.Tn POSIX
1277standard.
1278.Sh AUTHORS
1279Keith Muller at the University of California, San Diego.
1280Luke Mewburn implemented
1281.Fl M .
1282