1.\" Copyright (c) 1992 Keith Muller. 2.\" Copyright (c) 1992, 1993 3.\" The Regents of the University of California. All rights reserved. 4.\" 5.\" This code is derived from software contributed to Berkeley by 6.\" Keith Muller of the University of California, San Diego. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)pax.1 8.4 (Berkeley) 4/18/94 33.\" $FreeBSD: src/bin/pax/pax.1,v 1.12.2.10 2003/02/23 17:46:34 keramida Exp $ 34.\" $DragonFly: src/bin/pax/pax.1,v 1.4 2007/10/20 17:56:46 swildner Exp $ 35.\" 36.Dd March 27, 2009 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 cdnvzO 45.Bk -words 46.Op Fl f Ar archive 47.Ek 48.Bk -words 49.Op Fl s Ar replstr 50.Ar ...\& 51.Ek 52.Bk -words 53.Op Fl U Ar user 54.Ar ...\& 55.Ek 56.Bk -words 57.Op Fl G Ar group 58.Ar ...\& 59.Ek 60.Bk -words 61.Oo 62.Fl T 63.Op Ar from_date 64.Op Ar ,to_date 65.Oc 66.Ar ...\& 67.Ek 68.Op Ar pattern ...\& 69.Nm 70.Fl r 71.Op Fl cdiknuvzDOYZ 72.Bk -words 73.Op Fl f Ar archive 74.Ek 75.Bk -words 76.Op Fl o Ar options 77.Ar ...\& 78.Ek 79.Bk -words 80.Op Fl p Ar string 81.Ar ...\& 82.Ek 83.Bk -words 84.Op Fl s Ar replstr 85.Ar ...\& 86.Ek 87.Op Fl E Ar limit 88.Bk -words 89.Op Fl U Ar user 90.Ar ...\& 91.Ek 92.Bk -words 93.Op Fl G Ar group 94.Ar ...\& 95.Ek 96.Bk -words 97.Oo 98.Fl T 99.Op Ar from_date 100.Op Ar ,to_date 101.Oc 102.Ar ...\& 103.Ek 104.Op Ar pattern ...\& 105.Nm 106.Fl w 107.Op Fl dituvzHLOPX 108.Bk -words 109.Op Fl b Ar blocksize 110.Ek 111.Oo 112.Op Fl a 113.Op Fl f Ar archive 114.Oc 115.Bk -words 116.Op Fl x Ar format 117.Ek 118.Bk -words 119.Op Fl s Ar replstr 120.Ar ...\& 121.Ek 122.Bk -words 123.Op Fl o Ar options 124.Ar ...\& 125.Ek 126.Bk -words 127.Op Fl U Ar user 128.Ar ...\& 129.Ek 130.Bk -words 131.Op Fl G Ar group 132.Ar ...\& 133.Ek 134.Bk -words 135.Op Fl B Ar bytes 136.Ek 137.Bk -words 138.Oo 139.Fl T 140.Op Ar from_date 141.Op Ar ,to_date 142.Op Ar /[c][m] 143.Oc 144.Ar ...\& 145.Ek 146.Op Ar 147.Nm 148.Fl r 149.Fl w 150.Op Fl diklntuvDHLOPXYZ 151.Bk -words 152.Op Fl p Ar string 153.Ar ...\& 154.Ek 155.Bk -words 156.Op Fl s Ar replstr 157.Ar ...\& 158.Ek 159.Bk -words 160.Op Fl U Ar user 161.Ar ...\& 162.Ek 163.Bk -words 164.Op Fl G Ar group 165.Ar ...\& 166.Ek 167.Bk -words 168.Oo 169.Fl T 170.Op Ar from_date 171.Op Ar ,to_date 172.Op Ar /[c][m] 173.Oc 174.Ar ...\& 175.Ek 176.Op Ar 177.Ar directory 178.Sh DESCRIPTION 179The 180.Nm 181utility will read, write, and list the members of an archive file, 182and will copy directory hierarchies. 183These operations are independent of the specific archive format, 184and support a wide variety of different archive formats. 185A list of supported archive formats can be found under the description of the 186.Fl x 187option. 188.Pp 189The presence of the 190.Fl r 191and the 192.Fl w 193options specifies which of the following functional modes 194.Nm 195will operate under: 196.Em list , read , write , 197and 198.Em copy . 199.Bl -tag -width 6n 200.It <none> 201.Em List . 202Write to 203.Dv standard output 204a table of contents of the members of the archive file read from 205.Dv standard input , 206whose pathnames match the specified 207.Ar patterns . 208The table of contents contains one filename per line 209and is written using single line buffering. 210.It Fl r 211.Em Read . 212Extract the members of the archive file read from the 213.Dv standard input , 214with pathnames matching the specified 215.Ar patterns . 216The archive format and blocking is automatically determined on input. 217When an extracted file is a directory, the entire file hierarchy 218rooted at that directory is extracted. 219All extracted files are created relative to the current file hierarchy. 220The setting of ownership, access and modification times, and file mode of 221the extracted files are discussed in more detail under the 222.Fl p 223option. 224.It Fl w 225.Em Write . 226Write an archive containing the 227.Ar file 228operands to 229.Dv standard output 230using the specified archive format. 231When no 232.Ar file 233operands are specified, a list of files to copy with one per line is read from 234.Dv standard input . 235When a 236.Ar file 237operand is also a directory, the entire file hierarchy rooted 238at that directory will be included. 239.It Fl r Fl w 240.Em Copy . 241Copy the 242.Ar file 243operands to the destination 244.Ar directory . 245When no 246.Ar file 247operands are specified, a list of files to copy with one per line is read from 248the 249.Dv standard input . 250When a 251.Ar file 252operand is also a directory the entire file 253hierarchy rooted at that directory will be included. 254The effect of the 255.Em copy 256is as if the copied files were written to an archive file and then 257subsequently extracted, except that there may be hard links between 258the original and the copied files (see the 259.Fl l 260option below). 261.Pp 262.Em Warning : 263The destination 264.Ar directory 265must not be one of the 266.Ar file 267operands or a member of a file hierarchy rooted at one of the 268.Ar file 269operands. 270The result of a 271.Em copy 272under these conditions is unpredictable. 273.El 274.Pp 275While processing a damaged archive during a 276.Em read 277or 278.Em list 279operation, 280.Nm 281will attempt to recover from media defects and will search through the archive 282to locate and process the largest number of archive members possible (see the 283.Fl E 284option for more details on error handling). 285.Sh OPERANDS 286The 287.Ar directory 288operand specifies a destination directory pathname. 289If the 290.Ar directory 291operand does not exist, or it is not writable by the user, 292or it is not of type directory, 293.Nm 294will exit with a non-zero exit status. 295.Pp 296The 297.Ar pattern 298operand is used to select one or more pathnames of archive members. 299Archive members are selected using the pattern matching notation described 300by 301.Xr fnmatch 3 . 302When the 303.Ar pattern 304operand is not supplied, all members of the archive will be selected. 305When a 306.Ar pattern 307matches a directory, the entire file hierarchy rooted at that directory will 308be selected. 309When a 310.Ar pattern 311operand does not select at least one archive member, 312.Nm 313will write these 314.Ar pattern 315operands in a diagnostic message to 316.Dv standard error 317and then exit with a non-zero exit status. 318.Pp 319The 320.Ar file 321operand specifies the pathname of a file to be copied or archived. 322When a 323.Ar file 324operand does not select at least one archive member, 325.Nm 326will write these 327.Ar file 328operand pathnames in a diagnostic message to 329.Dv standard error 330and then exit with a non-zero exit status. 331.Sh OPTIONS 332The following options are supported: 333.Bl -tag -width 4n 334.It Fl r 335Read an archive file from 336.Dv standard input 337and extract the specified 338.Ar files . 339If any intermediate directories are needed in order to extract an archive 340member, these directories will be created as if 341.Xr mkdir 2 342was called with the bitwise inclusive 343.Dv OR 344of 345.Dv S_IRWXU , S_IRWXG , 346and 347.Dv S_IRWXO 348as the mode argument. 349When the selected archive format supports the specification of linked 350files and these files cannot be linked while the archive is being extracted, 351.Nm 352will write a diagnostic message to 353.Dv standard error 354and exit with a non-zero exit status at the completion of operation. 355.It Fl w 356Write files to the 357.Dv standard output 358in the specified archive format. 359When no 360.Ar file 361operands are specified, 362.Dv standard input 363is read for a list of pathnames with one per line without any leading or 364trailing 365.Aq blanks . 366.It Fl a 367Append 368.Ar files 369to the end of an archive that was previously written. 370If an archive format is not specified with a 371.Fl x 372option, the format currently being used in the archive will be selected. 373Any attempt to append to an archive in a format different from the 374format already used in the archive will cause 375.Nm 376to exit immediately 377with a non-zero exit status. 378The blocking size used in the archive volume where writing starts 379will continue to be used for the remainder of that archive volume. 380.Pp 381.Em Warning : 382Many storage devices are not able to support the operations necessary 383to perform an append operation. 384Any attempt to append to an archive stored on such a device may damage the 385archive or have other unpredictable results. 386Tape drives in particular are more likely to not support an append operation. 387An archive stored in a regular file system file or on a disk device will 388usually support an append operation. 389.It Fl b Ar blocksize 390When 391.Em writing 392an archive, 393block the output at a positive decimal integer number of 394bytes per write to the archive file. 395The 396.Ar blocksize 397must be a multiple of 512 bytes with a maximum of 64512 bytes. 398Archives larger than 32256 bytes violate the 399.Tn POSIX 400standard and will not be portable to all systems. 401A 402.Ar blocksize 403can end with 404.Li k 405or 406.Li b 407to specify multiplication by 1024 (1K) or 512, respectively. 408A pair of 409.Ar blocksizes 410can be separated by 411.Li x 412to indicate a product. 413A specific archive device may impose additional restrictions on the size 414of blocking it will support. 415When blocking is not specified, the default 416.Ar blocksize 417is dependent on the specific archive format being used (see the 418.Fl x 419option). 420.It Fl c 421Match all file or archive members 422.Em except 423those specified by the 424.Ar pattern 425and 426.Ar file 427operands. 428.It Fl d 429Cause files of type directory being copied or archived, or archive members of 430type directory being extracted, to match only the directory file or archive 431member and not the file hierarchy rooted at the directory. 432.It Fl f Ar archive 433Specify 434.Ar archive 435as the pathname of the input or output archive, overriding the default 436.Dv standard input 437(for 438.Em list 439and 440.Em read ) 441or 442.Dv standard output 443(for 444.Em write ) . 445A single archive may span multiple files and different archive devices. 446When required, 447.Nm 448will prompt for the pathname of the file or device of the next volume in the 449archive. 450.It Fl i 451Interactively rename files or archive members. 452For each archive member matching a 453.Ar pattern 454operand or each file matching a 455.Ar file 456operand, 457.Nm 458will prompt to 459.Pa /dev/tty 460giving the name of the file, its file mode and its modification time. 461The 462.Nm 463utility will then read a line from 464.Pa /dev/tty . 465If this line is blank, the file or archive member is skipped. 466If this line consists of a single period, the 467file or archive member is processed with no modification to its name. 468Otherwise, its name is replaced with the contents of the line. 469The 470.Nm 471utility will immediately exit with a non-zero exit status if 472.Dv <EOF> 473is encountered when reading a response or if 474.Pa /dev/tty 475cannot be opened for reading and writing. 476.It Fl k 477Do not overwrite existing files. 478.It Fl l 479Link files. 480(The letter ell). 481In the 482.Em copy 483mode 484.Pq Fl r w , 485hard links are made between the source and destination file hierarchies 486whenever possible. 487.It Fl n 488Select the first archive member that matches each 489.Ar pattern 490operand. 491No more than one archive member is matched for each 492.Ar pattern . 493When members of type directory are matched, the file hierarchy rooted at that 494directory is also matched (unless 495.Fl d 496is also specified). 497.It Fl o Ar options 498Information to modify the algorithm for extracting or writing archive files 499which is specific to the archive format specified by 500.Fl x . 501In general, 502.Ar options 503take the form: 504.Cm name=value 505.It Fl p Ar string 506Specify one or more file characteristic options (privileges). 507The 508.Ar string 509option-argument is a string specifying file characteristics to be retained or 510discarded on extraction. 511The string consists of the specification characters 512.Cm a , e , m , o , 513and 514.Cm p . 515Multiple characteristics can be concatenated within the same string 516and multiple 517.Fl p 518options can be specified. 519The meaning of the specification characters are as follows: 520.Bl -tag -width 2n 521.It Cm a 522Do not preserve file access times. 523By default, file access times are preserved whenever possible. 524.It Cm e 525.Sq Preserve everything , 526the user ID, group ID, file mode bits, 527file access time, and file modification time. 528This is intended to be used by 529.Em root , 530someone with all the appropriate privileges, in order to preserve all 531aspects of the files as they are recorded in the archive. 532The 533.Cm e 534flag is the sum of the 535.Cm o 536and 537.Cm p 538flags. 539.It Cm m 540Do not preserve file modification times. 541By default, file modification times are preserved whenever possible. 542.It Cm o 543Preserve the user ID and group ID. 544.It Cm p 545.Sq Preserve 546the file mode bits. 547This intended to be used by a 548.Em user 549with regular privileges who wants to preserve all aspects of the file other 550than the ownership. 551The file times are preserved by default, but two other flags are offered to 552disable this and use the time of extraction instead. 553.El 554.Pp 555In the preceding list, 556.Sq preserve 557indicates that an attribute stored in the archive is given to the 558extracted file, subject to the permissions of the invoking 559process. 560Otherwise the attribute of the extracted file is determined as 561part of the normal file creation action. 562If neither the 563.Cm e 564nor the 565.Cm o 566specification character is specified, or the user ID and group ID are not 567preserved for any reason, 568.Nm 569will not set the 570.Dv S_ISUID 571.Em ( setuid ) 572and 573.Dv S_ISGID 574.Em ( setgid ) 575bits of the file mode. 576If the preservation of any of these items fails for any reason, 577.Nm 578will write a diagnostic message to 579.Dv standard error . 580Failure to preserve these items will affect the final exit status, 581but will not cause the extracted file to be deleted. 582If the file characteristic letters in any of the string option-arguments are 583duplicated or conflict with each other, the one(s) given last will take 584precedence. 585For example, if 586.Dl Fl p Ar eme 587is specified, file modification times are still preserved. 588.It Fl s Ar replstr 589Modify the file or archive member names specified by the 590.Ar pattern 591or 592.Ar file 593operands according to the substitution expression 594.Ar replstr , 595using the syntax of the 596.Xr ed 1 597utility regular expressions. 598The format of these regular expressions are: 599.Dl /old/new/[gp] 600As in 601.Xr ed 1 , 602.Cm old 603is a basic regular expression and 604.Cm new 605can contain an ampersand (&), \\n (where n is a digit) back-references, 606or subexpression matching. 607The 608.Cm old 609string may also contain 610.Dv <newline> 611characters. 612Any non-null character can be used as a delimiter (/ is shown here). 613Multiple 614.Fl s 615expressions can be specified. 616The expressions are applied in the order they are specified on the 617command line, terminating with the first successful substitution. 618The optional trailing 619.Cm g 620continues to apply the substitution expression to the pathname substring 621which starts with the first character following the end of the last successful 622substitution. 623The first unsuccessful substitution stops the operation of the 624.Cm g 625option. 626The optional trailing 627.Cm p 628will cause the final result of a successful substitution to be written to 629.Dv standard error 630in the following format: 631.Dl <original pathname> >> <new pathname> 632File or archive member names that substitute to the empty string 633are not selected and will be skipped. 634.It Fl t 635Reset the access times of any file or directory read or accessed by 636.Nm 637to be the same as they were before being read or accessed by 638.Nm . 639.It Fl u 640Ignore files that are older (having a less recent file modification time) 641than a pre-existing file or archive member with the same name. 642During 643.Em read , 644an archive member with the same name as a file in the file system will be 645extracted if the archive member is newer than the file. 646During 647.Em write , 648a file system member with the same name as an archive member will be 649written to the archive if it is newer than the archive member. 650During 651.Em copy , 652the file in the destination hierarchy is replaced by the file in the source 653hierarchy or by a link to the file in the source hierarchy if the file in 654the source hierarchy is newer. 655.It Fl v 656During a 657.Em list 658operation, produce a verbose table of contents using the format of the 659.Xr ls 1 660utility with the 661.Fl l 662option. 663For pathnames representing a hard link to a previous member of the archive, 664the output has the format: 665.Dl <ls -l listing> == <link name> 666For pathnames representing a symbolic link, the output has the format: 667.Dl <ls -l listing> => <link name> 668Where <ls -l listing> is the output format specified by the 669.Xr ls 1 670utility when used with the 671.Fl l 672option. 673Otherwise for all the other operational modes 674.Em ( read , write , 675and 676.Em copy ) , 677pathnames are written and flushed to 678.Dv standard error 679without a trailing 680.Dv <newline> 681as soon as processing begins on that file or 682archive member. 683The trailing 684.Dv <newline> , 685is not buffered, and is written only after the file has been read or written. 686.It Fl x Ar format 687Specify the output archive format, with the default format being 688.Ar ustar . 689The 690.Nm 691utility currently supports the following formats: 692.Bl -tag -width "sv4cpio" 693.It Ar cpio 694The extended cpio interchange format specified in the 695.St -p1003.2 696standard. 697The default blocksize for this format is 5120 bytes. 698Inode and device information about a file (used for detecting file hard links 699by this format) which may be truncated by this format is detected by 700.Nm 701and is repaired. 702.It Ar bcpio 703The old binary cpio format. 704The default blocksize for this format is 5120 bytes. 705This format is not very portable and should not be used when other formats 706are available. 707Inode and device information about a file (used for detecting file hard links 708by this format) which may be truncated by this format is detected by 709.Nm 710and is repaired. 711.It Ar sv4cpio 712The System V release 4 cpio. 713The default blocksize for this format is 5120 bytes. 714Inode and device information about a file (used for detecting file hard links 715by this format) which may be truncated by this format is detected by 716.Nm 717and is repaired. 718.It Ar sv4crc 719The System V release 4 cpio with file crc checksums. 720The default blocksize for this format is 5120 bytes. 721Inode and device information about a file (used for detecting file hard links 722by this format) which may be truncated by this format is detected by 723.Nm 724and is repaired. 725.It Ar tar 726The old 727.Bx 728tar format as found in 729.Bx 4.3 . 730The default blocksize for this format is 10240 bytes. 731Pathnames stored by this format must be 100 characters or less in length. 732Only 733.Em regular 734files, 735.Em hard links , soft links , 736and 737.Em directories 738will be archived (other file system types are not supported). 739For backwards compatibility with even older tar formats, a 740.Fl o 741option can be used when writing an archive to omit the storage of directories. 742This option takes the form: 743.Dl Fl o Cm write_opt=nodir 744.It Ar ustar 745The extended tar interchange format specified in the 746.St -p1003.2 747standard. 748The default blocksize for this format is 10240 bytes. 749Pathnames stored by this format must be 250 characters or less in length. 750.El 751.Pp 752The 753.Nm 754utility will detect and report any file that it is unable to store or extract 755as the result of any specific archive format restrictions. 756The individual archive formats may impose additional restrictions on use. 757Typical archive format restrictions include (but are not limited to): 758file pathname length, file size, link pathname length and the type of the file. 759.It Fl z 760Use 761.Xr gzip 1 762to compress (decompress) the archive while writing (reading). 763Incompatible with 764.Fl a . 765.It Fl B Ar bytes 766Limit the number of bytes written to a single archive volume to 767.Ar bytes . 768The 769.Ar bytes 770limit can end with 771.Li m , 772.Li k , 773or 774.Li b 775to specify multiplication by 1048576 (1M), 1024 (1K) or 512, respectively. 776A pair of 777.Ar bytes 778limits can be separated by 779.Li x 780to indicate a product. 781.Pp 782.Em Warning : 783Only use this option when writing an archive to a device which supports 784an end of file read condition based on last (or largest) write offset 785(such as a regular file or a tape drive). 786The use of this option with a floppy or hard disk is not recommended. 787.It Fl D 788This option is the same as the 789.Fl u 790option, except that the file inode change time is checked instead of the 791file modification time. 792The file inode change time can be used to select files whose inode information 793(e.g. uid, gid, etc.) is newer than a copy of the file in the destination 794.Ar directory . 795.It Fl E Ar limit 796Limit the number of consecutive read faults while trying to read a flawed 797archives to 798.Ar limit . 799With a positive 800.Ar limit , 801.Nm 802will attempt to recover from an archive read error and will 803continue processing starting with the next file stored in the archive. 804A 805.Ar limit 806of 0 will cause 807.Nm 808to stop operation after the first read error is detected on an archive volume. 809A 810.Ar limit 811of 812.Li NONE 813will cause 814.Nm 815to attempt to recover from read errors forever. 816The default 817.Ar limit 818is a small positive number of retries. 819.Pp 820.Em Warning : 821Using this option with 822.Li NONE 823should be used with extreme caution as 824.Nm 825may get stuck in an infinite loop on a very badly flawed archive. 826.It Fl G Ar group 827Select a file based on its 828.Ar group 829name, or when starting with a 830.Cm # , 831a numeric gid. 832A '\\' can be used to escape the 833.Cm # . 834Multiple 835.Fl G 836options may be supplied and checking stops with the first match. 837.It Fl H 838Follow only command line symbolic links while performing a physical file 839system traversal. 840.It Fl L 841Follow all symbolic links to perform a logical file system traversal. 842.It Fl O 843Force the archive to be one volume. If a volume ends prematurely, 844.Nm 845will not prompt for a new volume. This option can be useful for 846automated tasks where error recovery cannot be performed by a human. 847.It Fl P 848Do not follow symbolic links, perform a physical file system traversal. 849This is the default mode. 850.It Fl T Ar [from_date][,to_date][/[c][m]] 851Allow files to be selected based on a file modification or inode change 852time falling within a specified time range of 853.Ar from_date 854to 855.Ar to_date 856(the dates are inclusive). 857If only a 858.Ar from_date 859is supplied, all files with a modification or inode change time 860equal to or younger are selected. 861If only a 862.Ar to_date 863is supplied, all files with a modification or inode change time 864equal to or older will be selected. 865When the 866.Ar from_date 867is equal to the 868.Ar to_date , 869only files with a modification or inode change time of exactly that 870time will be selected. 871.Pp 872When 873.Nm 874is in the 875.Em write 876or 877.Em copy 878mode, the optional trailing field 879.Ar [c][m] 880can be used to determine which file time (inode change, file modification or 881both) are used in the comparison. 882If neither is specified, the default is to use file modification time only. 883The 884.Ar m 885specifies the comparison of file modification time (the time when 886the file was last written). 887The 888.Ar c 889specifies the comparison of inode change time (the time when the file 890inode was last changed; e.g. a change of owner, group, mode, etc). 891When 892.Ar c 893and 894.Ar m 895are both specified, then the modification and inode change times are 896both compared. 897The inode change time comparison is useful in selecting files whose 898attributes were recently changed or selecting files which were recently 899created and had their modification time reset to an older time (as what 900happens when a file is extracted from an archive and the modification time 901is preserved). 902Time comparisons using both file times is useful when 903.Nm 904is used to create a time based incremental archive (only files that were 905changed during a specified time range will be archived). 906.Pp 907A time range is made up of six different fields and each field must contain two 908digits. 909The format is: 910.Dl [yy[mm[dd[hh]]]]mm[.ss] 911Where 912.Cm yy 913is the last two digits of the year, 914the first 915.Cm mm 916is the month (from 01 to 12), 917.Cm dd 918is the day of the month (from 01 to 31), 919.Cm hh 920is the hour of the day (from 00 to 23), 921the second 922.Cm mm 923is the minute (from 00 to 59), 924and 925.Cm ss 926is the seconds (from 00 to 59). 927The minute field 928.Cm mm 929is required, while the other fields are optional and must be added in the 930following order: 931.Dl Cm hh , dd , mm , yy . 932The 933.Cm ss 934field may be added independently of the other fields. 935Time ranges are relative to the current time, so 936.Dl Fl T Ar 1234/cm 937would select all files with a modification or inode change time 938of 12:34 PM today or later. 939Multiple 940.Fl T 941time range can be supplied and checking stops with the first match. 942.It Fl U Ar user 943Select a file based on its 944.Ar user 945name, or when starting with a 946.Cm # , 947a numeric uid. 948A '\\' can be used to escape the 949.Cm # . 950Multiple 951.Fl U 952options may be supplied and checking stops with the first match. 953.It Fl X 954When traversing the file hierarchy specified by a pathname, 955do not descend into directories that have a different device ID. 956See the 957.Li st_dev 958field as described in 959.Xr stat 2 960for more information about device ID's. 961.It Fl Y 962This option is the same as the 963.Fl D 964option, except that the inode change time is checked using the 965pathname created after all the file name modifications have completed. 966.It Fl Z 967This option is the same as the 968.Fl u 969option, except that the modification time is checked using the 970pathname created after all the file name modifications have completed. 971.El 972.Pp 973The options that operate on the names of files or archive members 974.Fl ( c , 975.Fl i , 976.Fl n , 977.Fl s , 978.Fl u , 979.Fl v , 980.Fl D , 981.Fl G , 982.Fl T , 983.Fl U , 984.Fl Y , 985and 986.Fl Z ) 987interact as follows. 988.Pp 989When extracting files during a 990.Em read 991operation, archive members are 992.Sq selected , 993based only on the user specified pattern operands as modified by the 994.Fl c , 995.Fl n , 996.Fl u , 997.Fl D , 998.Fl G , 999.Fl T , 1000.Fl U 1001options. 1002Then any 1003.Fl s 1004and 1005.Fl i 1006options will modify in that order, the names of these selected files. 1007Then the 1008.Fl Y 1009and 1010.Fl Z 1011options will be applied based on the final pathname. 1012Finally the 1013.Fl v 1014option will write the names resulting from these modifications. 1015.Pp 1016When archiving files during a 1017.Em write 1018operation, or copying files during a 1019.Em copy 1020operation, archive members are 1021.Sq selected , 1022based only on the user specified pathnames as modified by the 1023.Fl n , 1024.Fl u , 1025.Fl D , 1026.Fl G , 1027.Fl T , 1028and 1029.Fl U 1030options (the 1031.Fl D 1032option only applies during a copy operation). 1033Then any 1034.Fl s 1035and 1036.Fl i 1037options will modify in that order, the names of these selected files. 1038Then during a 1039.Em copy 1040operation the 1041.Fl Y 1042and the 1043.Fl Z 1044options will be applied based on the final pathname. 1045Finally the 1046.Fl v 1047option will write the names resulting from these modifications. 1048.Pp 1049When one or both of the 1050.Fl u 1051or 1052.Fl D 1053options are specified along with the 1054.Fl n 1055option, a file is not considered selected unless it is newer 1056than the file to which it is compared. 1057.Sh EXAMPLES 1058The command: 1059.Dl "pax -w -f /dev/rst0 ." 1060copies the contents of the current directory to the device 1061.Pa /dev/rst0 . 1062.Pp 1063The command: 1064.Dl pax -v -f filename 1065gives the verbose table of contents for an archive stored in 1066.Pa filename . 1067.Pp 1068The following commands: 1069.Dl mkdir /tmp/to 1070.Dl cd /tmp/from 1071.Dl pax -rw .\ /tmp/to 1072will copy the entire 1073.Pa /tmp/from 1074directory hierarchy to 1075.Pa /tmp/to . 1076.Pp 1077The command: 1078.Dl pax -r -s ',^//*usr//*,,' -f a.pax 1079reads the archive 1080.Pa a.pax , 1081with all files rooted in ``/usr'' into the archive extracted relative to the 1082current directory. 1083.Pp 1084The command: 1085.Dl pax -rw -i .\ dest_dir 1086can be used to interactively select the files to copy from the current 1087directory to 1088.Pa dest_dir . 1089.Pp 1090The command: 1091.Dl pax -r -pe -U root -G bin -f a.pax 1092will extract all files from the archive 1093.Pa a.pax 1094which are owned by 1095.Em root 1096with group 1097.Em bin 1098and will preserve all file permissions. 1099.Pp 1100The command: 1101.Dl pax -r -w -v -Y -Z home /backup 1102will update (and list) only those files in the destination directory 1103.Pa /backup 1104which are older (less recent inode change or file modification times) than 1105files with the same name found in the source file tree 1106.Pa home . 1107.Sh DIAGNOSTICS 1108The 1109.Nm 1110utility will exit with one of the following values: 1111.Bl -tag -width 2n 1112.It 0 1113All files were processed successfully. 1114.It 1 1115An error occurred. 1116.El 1117.Pp 1118Whenever 1119.Nm 1120cannot create a file or a link when reading an archive or cannot 1121find a file when writing an archive, or cannot preserve the user ID, 1122group ID, or file mode when the 1123.Fl p 1124option is specified, a diagnostic message is written to 1125.Dv standard error 1126and a non-zero exit status will be returned, but processing will continue. 1127In the case where 1128.Nm 1129cannot create a link to a file, 1130.Nm 1131will not create a second copy of the file. 1132.Pp 1133If the extraction of a file from an archive is prematurely terminated by 1134a signal or error, 1135.Nm 1136may have only partially extracted a file the user wanted. 1137Additionally, the file modes of extracted files and directories 1138may have incorrect file bits, and the modification and access times may be 1139wrong. 1140.Pp 1141If the creation of an archive is prematurely terminated by a signal or error, 1142.Nm 1143may have only partially created the archive which may violate the specific 1144archive format specification. 1145.Pp 1146If while doing a 1147.Em copy , 1148.Nm 1149detects a file is about to overwrite itself, the file is not copied, 1150a diagnostic message is written to 1151.Dv standard error 1152and when 1153.Nm 1154completes it will exit with a non-zero exit status. 1155.Sh SEE ALSO 1156.Xr cpio 1 , 1157.Xr tar 1 1158.Sh STANDARDS 1159The 1160.Nm 1161utility is a superset of the 1162.St -p1003.2 1163standard. 1164The options 1165.Fl z , 1166.Fl B , 1167.Fl D , 1168.Fl E , 1169.Fl G , 1170.Fl H , 1171.Fl L , 1172.Fl O , 1173.Fl P , 1174.Fl T , 1175.Fl U , 1176.Fl Y , 1177.Fl Z , 1178the archive formats 1179.Ar bcpio , 1180.Ar sv4cpio , 1181.Ar sv4crc , 1182.Ar tar , 1183and the flawed archive handling during 1184.Ar list 1185and 1186.Ar read 1187operations are extensions to the 1188.Tn POSIX 1189standard. 1190.Sh HISTORY 1191The 1192.Nm 1193utility appeared in 1194.Bx 4.4 . 1195.Sh AUTHORS 1196.An Keith Muller 1197at the University of California, San Diego 1198