1.\"- 2.\" Copyright (c) 1992 Keith Muller. 3.\" Copyright (c) 1992, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" This code is derived from software contributed to Berkeley by 7.\" Keith Muller of the University of California, San Diego. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 4. Neither the name of the University nor the names of its contributors 18.\" may be used to endorse or promote products derived from this software 19.\" without specific prior written permission. 20.\" 21.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31.\" SUCH DAMAGE. 32.\" 33.\" @(#)pax.1 8.4 (Berkeley) 4/18/94 34.\" $FreeBSD$ 35.\" 36.Dd July 3, 2004 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 cdnvz 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 cdiknuvzDYZ 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 dituvzHLPX 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 diklntuvDHLPXYZ 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. 398A 399.Ar blocksize 400larger than 32256 bytes violates the 401.Tn POSIX 402standard and will not be portable to all systems. 403A 404.Ar blocksize 405can end with 406.Li k 407or 408.Li b 409to specify multiplication by 1024 (1K) or 512, respectively. 410A pair of 411.Ar blocksizes 412can be separated by 413.Li x 414to indicate a product. 415A specific archive device may impose additional restrictions on the size 416of blocking it will support. 417When blocking is not specified, the default 418.Ar blocksize 419is dependent on the specific archive format being used (see the 420.Fl x 421option). 422.It Fl c 423Match all file or archive members 424.Em except 425those specified by the 426.Ar pattern 427and 428.Ar file 429operands. 430.It Fl d 431Cause files of type directory being copied or archived, or archive members of 432type directory being extracted, to match only the directory file or archive 433member and not the file hierarchy rooted at the directory. 434.It Fl f Ar archive 435Specify 436.Ar archive 437as the pathname of the input or output archive, overriding the default 438.Dv standard input 439(for 440.Em list 441and 442.Em read ) 443or 444.Dv standard output 445(for 446.Em write ) . 447A single archive may span multiple files and different archive devices. 448When required, 449.Nm 450will prompt for the pathname of the file or device of the next volume in the 451archive. 452.It Fl i 453Interactively rename files or archive members. 454For each archive member matching a 455.Ar pattern 456operand or each file matching a 457.Ar file 458operand, 459.Nm 460will prompt to 461.Pa /dev/tty 462giving the name of the file, its file mode and its modification time. 463The 464.Nm 465utility will then read a line from 466.Pa /dev/tty . 467If this line is blank, the file or archive member is skipped. 468If this line consists of a single period, the 469file or archive member is processed with no modification to its name. 470Otherwise, its name is replaced with the contents of the line. 471The 472.Nm 473utility will immediately exit with a non-zero exit status if 474.Dv <EOF> 475is encountered when reading a response or if 476.Pa /dev/tty 477cannot be opened for reading and writing. 478.It Fl k 479Do not overwrite existing files. 480.It Fl l 481Link files. 482(The letter ell). 483In the 484.Em copy 485mode 486.Pq Fl r w , 487hard links are made between the source and destination file hierarchies 488whenever possible. 489.It Fl n 490Select the first archive member that matches each 491.Ar pattern 492operand. 493No more than one archive member is matched for each 494.Ar pattern . 495When members of type directory are matched, the file hierarchy rooted at that 496directory is also matched (unless 497.Fl d 498is also specified). 499.It Fl o Ar options 500Information to modify the algorithm for extracting or writing archive files 501which is specific to the archive format specified by 502.Fl x . 503In general, 504.Ar options 505take the form: 506.Cm name=value 507.It Fl p Ar string 508Specify one or more file characteristic options (privileges). 509The 510.Ar string 511option-argument is a string specifying file characteristics to be retained or 512discarded on extraction. 513The string consists of the specification characters 514.Cm a , e , m , o , 515and 516.Cm p . 517Multiple characteristics can be concatenated within the same string 518and multiple 519.Fl p 520options can be specified. 521The meaning of the specification characters are as follows: 522.Bl -tag -width 2n 523.It Cm a 524Do not preserve file access times. 525By default, file access times are preserved whenever possible. 526.It Cm e 527.Sq Preserve everything , 528the user ID, group ID, file mode bits, 529file access time, and file modification time. 530This is intended to be used by 531.Em root , 532someone with all the appropriate privileges, in order to preserve all 533aspects of the files as they are recorded in the archive. 534The 535.Cm e 536flag is the sum of the 537.Cm o 538and 539.Cm p 540flags. 541.It Cm m 542Do not preserve file modification times. 543By default, file modification times are preserved whenever possible. 544.It Cm o 545Preserve the user ID and group ID. 546.It Cm p 547.Sq Preserve 548the file mode bits. 549This intended to be used by a 550.Em user 551with regular privileges who wants to preserve all aspects of the file other 552than the ownership. 553The file times are preserved by default, but two other flags are offered to 554disable this and use the time of extraction instead. 555.El 556.Pp 557In the preceding list, 558.Sq preserve 559indicates that an attribute stored in the archive is given to the 560extracted file, subject to the permissions of the invoking 561process. 562Otherwise the attribute of the extracted file is determined as 563part of the normal file creation action. 564If neither the 565.Cm e 566nor the 567.Cm o 568specification character is specified, or the user ID and group ID are not 569preserved for any reason, 570.Nm 571will not set the 572.Dv S_ISUID 573.Em ( setuid ) 574and 575.Dv S_ISGID 576.Em ( setgid ) 577bits of the file mode. 578If the preservation of any of these items fails for any reason, 579.Nm 580will write a diagnostic message to 581.Dv standard error . 582Failure to preserve these items will affect the final exit status, 583but will not cause the extracted file to be deleted. 584If the file characteristic letters in any of the string option-arguments are 585duplicated or conflict with each other, the one(s) given last will take 586precedence. 587For example, if 588.Dl Fl p Ar eme 589is specified, file modification times are still preserved. 590.It Fl s Ar replstr 591Modify the file or archive member names specified by the 592.Ar pattern 593or 594.Ar file 595operands according to the substitution expression 596.Ar replstr , 597using the syntax of the 598.Xr ed 1 599utility regular expressions. 600The format of these regular expressions are: 601.Dl /old/new/[gp] 602As in 603.Xr ed 1 , 604.Cm old 605is a basic regular expression and 606.Cm new 607can contain an ampersand (&), \\n (where n is a digit) back-references, 608or subexpression matching. 609The 610.Cm old 611string may also contain 612.Dv <newline> 613characters. 614Any non-null character can be used as a delimiter (/ is shown here). 615Multiple 616.Fl s 617expressions can be specified. 618The expressions are applied in the order they are specified on the 619command line, terminating with the first successful substitution. 620The optional trailing 621.Cm g 622continues to apply the substitution expression to the pathname substring 623which starts with the first character following the end of the last successful 624substitution. 625The first unsuccessful substitution stops the operation of the 626.Cm g 627option. 628The optional trailing 629.Cm p 630will cause the final result of a successful substitution to be written to 631.Dv standard error 632in the following format: 633.Dl <original pathname> >> <new pathname> 634File or archive member names that substitute to the empty string 635are not selected and will be skipped. 636.It Fl t 637Reset the access times of any file or directory read or accessed by 638.Nm 639to be the same as they were before being read or accessed by 640.Nm . 641.It Fl u 642Ignore files that are older (having a less recent file modification time) 643than a pre-existing file or archive member with the same name. 644During 645.Em read , 646an archive member with the same name as a file in the file system will be 647extracted if the archive member is newer than the file. 648During 649.Em write , 650a file system member with the same name as an archive member will be 651written to the archive if it is newer than the archive member. 652During 653.Em copy , 654the file in the destination hierarchy is replaced by the file in the source 655hierarchy or by a link to the file in the source hierarchy if the file in 656the source hierarchy is newer. 657.It Fl v 658During a 659.Em list 660operation, produce a verbose table of contents using the format of the 661.Xr ls 1 662utility with the 663.Fl l 664option. 665For pathnames representing a hard link to a previous member of the archive, 666the output has the format: 667.Dl <ls -l listing> == <link name> 668For pathnames representing a symbolic link, the output has the format: 669.Dl <ls -l listing> => <link name> 670Where <ls -l listing> is the output format specified by the 671.Xr ls 1 672utility when used with the 673.Fl l 674option. 675Otherwise for all the other operational modes 676.Em ( read , write , 677and 678.Em copy ) , 679pathnames are written and flushed to 680.Dv standard error 681without a trailing 682.Dv <newline> 683as soon as processing begins on that file or 684archive member. 685The trailing 686.Dv <newline> , 687is not buffered, and is written only after the file has been read or written. 688.It Fl x Ar format 689Specify the output archive format, with the default format being 690.Ar ustar . 691The 692.Nm 693utility currently supports the following formats: 694.Bl -tag -width "sv4cpio" 695.It Ar cpio 696The extended cpio interchange format specified in the 697.St -p1003.2 698standard. 699The default blocksize for this format is 5120 bytes. 700Inode and device information about a file (used for detecting file hard links 701by this format) which may be truncated by this format is detected by 702.Nm 703and is repaired. 704.It Ar bcpio 705The old binary cpio format. 706The default blocksize for this format is 5120 bytes. 707This format is not very portable and should not be used when other formats 708are available. 709Inode and device information about a file (used for detecting file hard links 710by this format) which may be truncated by this format is detected by 711.Nm 712and is repaired. 713.It Ar sv4cpio 714The System V release 4 cpio. 715The default blocksize for this format is 5120 bytes. 716Inode and device information about a file (used for detecting file hard links 717by this format) which may be truncated by this format is detected by 718.Nm 719and is repaired. 720.It Ar sv4crc 721The System V release 4 cpio with file crc checksums. 722The default blocksize for this format is 5120 bytes. 723Inode and device information about a file (used for detecting file hard links 724by this format) which may be truncated by this format is detected by 725.Nm 726and is repaired. 727.It Ar tar 728The old 729.Bx 730tar format as found in 731.Bx 4.3 . 732The default blocksize for this format is 10240 bytes. 733Pathnames stored by this format must be 100 characters or less in length. 734Only 735.Em regular 736files, 737.Em hard links , soft links , 738and 739.Em directories 740will be archived (other file system types are not supported). 741For backwards compatibility with even older tar formats, a 742.Fl o 743option can be used when writing an archive to omit the storage of directories. 744This option takes the form: 745.Dl Fl o Cm write_opt=nodir 746.It Ar ustar 747The extended tar interchange format specified in the 748.St -p1003.2 749standard. 750The default blocksize for this format is 10240 bytes. 751Pathnames stored by this format must be 250 characters or less in length. 752.El 753.Pp 754The 755.Nm 756utility will detect and report any file that it is unable to store or extract 757as the result of any specific archive format restrictions. 758The individual archive formats may impose additional restrictions on use. 759Typical archive format restrictions include (but are not limited to): 760file pathname length, file size, link pathname length and the type of the file. 761.It Fl z 762Use 763.Xr gzip 1 764to compress (decompress) the archive while writing (reading). 765Incompatible with 766.Fl a . 767.It Fl B Ar bytes 768Limit the number of bytes written to a single archive volume to 769.Ar bytes . 770The 771.Ar bytes 772limit can end with 773.Li m , 774.Li k , 775or 776.Li b 777to specify multiplication by 1048576 (1M), 1024 (1K) or 512, respectively. 778A pair of 779.Ar bytes 780limits can be separated by 781.Li x 782to indicate a product. 783.Pp 784.Em Warning : 785Only use this option when writing an archive to a device which supports 786an end of file read condition based on last (or largest) write offset 787(such as a regular file or a tape drive). 788The use of this option with a floppy or hard disk is not recommended. 789.It Fl D 790This option is the same as the 791.Fl u 792option, except that the file inode change time is checked instead of the 793file modification time. 794The file inode change time can be used to select files whose inode information 795(e.g.\& uid, gid, etc.) is newer than a copy of the file in the destination 796.Ar directory . 797.It Fl E Ar limit 798Limit the number of consecutive read faults while trying to read a flawed 799archives to 800.Ar limit . 801With a positive 802.Ar limit , 803.Nm 804will attempt to recover from an archive read error and will 805continue processing starting with the next file stored in the archive. 806A 807.Ar limit 808of 0 will cause 809.Nm 810to stop operation after the first read error is detected on an archive volume. 811A 812.Ar limit 813of 814.Li NONE 815will cause 816.Nm 817to attempt to recover from read errors forever. 818The default 819.Ar limit 820is a small positive number of retries. 821.Pp 822.Em Warning : 823Using this option with 824.Li NONE 825should be used with extreme caution as 826.Nm 827may get stuck in an infinite loop on a very badly flawed archive. 828.It Fl G Ar group 829Select a file based on its 830.Ar group 831name, or when starting with a 832.Cm # , 833a numeric gid. 834A '\\' can be used to escape the 835.Cm # . 836Multiple 837.Fl G 838options may be supplied and checking stops with the first match. 839.It Fl H 840Follow only command line symbolic links while performing a physical file 841system traversal. 842.It Fl L 843Follow all symbolic links to perform a logical file system traversal. 844.It Fl P 845Do not follow symbolic links, perform a physical file system traversal. 846This is the default mode. 847.It Fl T Ar [from_date][,to_date][/[c][m]] 848Allow files to be selected based on a file modification or inode change 849time falling within a specified time range of 850.Ar from_date 851to 852.Ar to_date 853(the dates are inclusive). 854If only a 855.Ar from_date 856is supplied, all files with a modification or inode change time 857equal to or younger are selected. 858If only a 859.Ar to_date 860is supplied, all files with a modification or inode change time 861equal to or older will be selected. 862When the 863.Ar from_date 864is equal to the 865.Ar to_date , 866only files with a modification or inode change time of exactly that 867time will be selected. 868.Pp 869When 870.Nm 871is in the 872.Em write 873or 874.Em copy 875mode, the optional trailing field 876.Ar [c][m] 877can be used to determine which file time (inode change, file modification or 878both) are used in the comparison. 879If neither is specified, the default is to use file modification time only. 880The 881.Ar m 882specifies the comparison of file modification time (the time when 883the file was last written). 884The 885.Ar c 886specifies the comparison of inode change time (the time when the file 887inode was last changed; e.g.\& a change of owner, group, mode, etc). 888When 889.Ar c 890and 891.Ar m 892are both specified, then the modification and inode change times are 893both compared. 894The inode change time comparison is useful in selecting files whose 895attributes were recently changed or selecting files which were recently 896created and had their modification time reset to an older time (as what 897happens when a file is extracted from an archive and the modification time 898is preserved). 899Time comparisons using both file times is useful when 900.Nm 901is used to create a time based incremental archive (only files that were 902changed during a specified time range will be archived). 903.Pp 904A time range is made up of six different fields and each field must contain two 905digits. 906The format is: 907.Dl [yy[mm[dd[hh]]]]mm[.ss] 908Where 909.Cm yy 910is the last two digits of the year, 911the first 912.Cm mm 913is the month (from 01 to 12), 914.Cm dd 915is the day of the month (from 01 to 31), 916.Cm hh 917is the hour of the day (from 00 to 23), 918the second 919.Cm mm 920is the minute (from 00 to 59), 921and 922.Cm ss 923is the seconds (from 00 to 59). 924The minute field 925.Cm mm 926is required, while the other fields are optional and must be added in the 927following order: 928.Dl Cm hh , dd , mm , yy . 929The 930.Cm ss 931field may be added independently of the other fields. 932Time ranges are relative to the current time, so 933.Dl Fl T Ar 1234/cm 934would select all files with a modification or inode change time 935of 12:34 PM today or later. 936Multiple 937.Fl T 938time range can be supplied and checking stops with the first match. 939.It Fl U Ar user 940Select a file based on its 941.Ar user 942name, or when starting with a 943.Cm # , 944a numeric uid. 945A '\\' can be used to escape the 946.Cm # . 947Multiple 948.Fl U 949options may be supplied and checking stops with the first match. 950.It Fl X 951When traversing the file hierarchy specified by a pathname, 952do not descend into directories that have a different device ID. 953See the 954.Li st_dev 955field as described in 956.Xr stat 2 957for more information about device ID's. 958.It Fl Y 959This option is the same as the 960.Fl D 961option, except that the inode change time is checked using the 962pathname created after all the file name modifications have completed. 963.It Fl Z 964This option is the same as the 965.Fl u 966option, except that the modification time is checked using the 967pathname created after all the file name modifications have completed. 968.El 969.Pp 970The options that operate on the names of files or archive members 971.Fl ( c , 972.Fl i , 973.Fl n , 974.Fl s , 975.Fl u , 976.Fl v , 977.Fl D , 978.Fl G , 979.Fl T , 980.Fl U , 981.Fl Y , 982and 983.Fl Z ) 984interact as follows. 985.Pp 986When extracting files during a 987.Em read 988operation, archive members are 989.Sq selected , 990based only on the user specified pattern operands as modified by the 991.Fl c , 992.Fl n , 993.Fl u , 994.Fl D , 995.Fl G , 996.Fl T , 997.Fl U 998options. 999Then any 1000.Fl s 1001and 1002.Fl i 1003options will modify in that order, the names of these selected files. 1004Then the 1005.Fl Y 1006and 1007.Fl Z 1008options will be applied based on the final pathname. 1009Finally the 1010.Fl v 1011option will write the names resulting from these modifications. 1012.Pp 1013When archiving files during a 1014.Em write 1015operation, or copying files during a 1016.Em copy 1017operation, archive members are 1018.Sq selected , 1019based only on the user specified pathnames as modified by the 1020.Fl n , 1021.Fl u , 1022.Fl D , 1023.Fl G , 1024.Fl T , 1025and 1026.Fl U 1027options (the 1028.Fl D 1029option only applies during a copy operation). 1030Then any 1031.Fl s 1032and 1033.Fl i 1034options will modify in that order, the names of these selected files. 1035Then during a 1036.Em copy 1037operation the 1038.Fl Y 1039and the 1040.Fl Z 1041options will be applied based on the final pathname. 1042Finally the 1043.Fl v 1044option will write the names resulting from these modifications. 1045.Pp 1046When one or both of the 1047.Fl u 1048or 1049.Fl D 1050options are specified along with the 1051.Fl n 1052option, a file is not considered selected unless it is newer 1053than the file to which it is compared. 1054.Sh EXIT STATUS 1055The 1056.Nm 1057utility will exit with one of the following values: 1058.Bl -tag -width 2n 1059.It 0 1060All files were processed successfully. 1061.It 1 1062An error occurred. 1063.El 1064.Sh EXAMPLES 1065The command: 1066.Dl "pax -w -f /dev/sa0 ." 1067copies the contents of the current directory to the device 1068.Pa /dev/sa0 . 1069.Pp 1070The command: 1071.Dl pax -v -f filename 1072gives the verbose table of contents for an archive stored in 1073.Pa filename . 1074.Pp 1075The following commands: 1076.Dl mkdir /tmp/to 1077.Dl cd /tmp/from 1078.Dl pax -rw .\ /tmp/to 1079will copy the entire 1080.Pa /tmp/from 1081directory hierarchy to 1082.Pa /tmp/to . 1083.Pp 1084The command: 1085.Dl pax -r -s ',^//*usr//*,,' -f a.pax 1086reads the archive 1087.Pa a.pax , 1088with all files rooted in ``/usr'' into the archive extracted relative to the 1089current directory. 1090.Pp 1091The command: 1092.Dl pax -rw -i .\ dest_dir 1093can be used to interactively select the files to copy from the current 1094directory to 1095.Pa dest_dir . 1096.Pp 1097The command: 1098.Dl pax -r -pe -U root -G bin -f a.pax 1099will extract all files from the archive 1100.Pa a.pax 1101which are owned by 1102.Em root 1103with group 1104.Em bin 1105and will preserve all file permissions. 1106.Pp 1107The command: 1108.Dl pax -r -w -v -Y -Z home /backup 1109will update (and list) only those files in the destination directory 1110.Pa /backup 1111which are older (less recent inode change or file modification times) than 1112files with the same name found in the source file tree 1113.Pa home . 1114.Sh DIAGNOSTICS 1115Whenever 1116.Nm 1117cannot create a file or a link when reading an archive or cannot 1118find a file when writing an archive, or cannot preserve the user ID, 1119group ID, or file mode when the 1120.Fl p 1121option is specified, a diagnostic message is written to 1122.Dv standard error 1123and a non-zero exit status will be returned, but processing will continue. 1124In the case where pax cannot create a link to a file, 1125.Nm 1126will not create a second copy of the file. 1127.Pp 1128If the extraction of a file from an archive is prematurely terminated by 1129a signal or error, 1130.Nm 1131may have only partially extracted a file the user wanted. 1132Additionally, the file modes of extracted files and directories 1133may have incorrect file bits, and the modification and access times may be 1134wrong. 1135.Pp 1136If the creation of an archive is prematurely terminated by a signal or error, 1137.Nm 1138may have only partially created the archive which may violate the specific 1139archive format specification. 1140.Pp 1141If while doing a 1142.Em copy , 1143.Nm 1144detects a file is about to overwrite itself, the file is not copied, 1145a diagnostic message is written to 1146.Dv standard error 1147and when 1148.Nm 1149completes it will exit with a non-zero exit status. 1150.Sh SEE ALSO 1151.Xr cpio 1 , 1152.Xr tar 1 1153.Sh STANDARDS 1154The 1155.Nm 1156utility is a superset of the 1157.St -p1003.2 1158standard. 1159The options 1160.Fl z , 1161.Fl B , 1162.Fl D , 1163.Fl E , 1164.Fl G , 1165.Fl H , 1166.Fl L , 1167.Fl P , 1168.Fl T , 1169.Fl U , 1170.Fl Y , 1171.Fl Z , 1172the archive formats 1173.Ar bcpio , 1174.Ar sv4cpio , 1175.Ar sv4crc , 1176.Ar tar , 1177and the flawed archive handling during 1178.Ar list 1179and 1180.Ar read 1181operations are extensions to the 1182.Tn POSIX 1183standard. 1184.Sh HISTORY 1185The 1186.Nm 1187utility appeared in 1188.Bx 4.4 . 1189.Sh AUTHORS 1190.An Keith Muller 1191at the University of California, San Diego 1192.Sh BUGS 1193The 1194.Nm 1195utility does not recognize multibyte characters. 1196