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.\" %sccs.include.redist.man% 9.\" 10.\" @(#)pax.1 8.4 (Berkeley) 04/18/94 11.\" 12.Dd 13.Dt PAX 1 14.Os BSD 4.4 15.Sh NAME 16.Nm pax 17.Nd read and write file archives and copy directory hierarchies 18.Sh SYNOPSIS 19.Nm pax 20.Op Fl cdnv 21.Bk -words 22.Op Fl f Ar archive 23.Ek 24.Bk -words 25.Op Fl s Ar replstr 26.Ar ... 27.Ek 28.Bk -words 29.Op Fl U Ar user 30.Ar ... 31.Ek 32.Bk -words 33.Op Fl G Ar group 34.Ar ... 35.Ek 36.Bk -words 37.Oo 38.Fl T 39.Op Ar from_date 40.Op Ar ,to_date 41.Oc 42.Ar ... 43.Ek 44.Op Ar pattern ... 45.Nm pax 46.Fl r 47.Op Fl cdiknuvDYZ 48.Bk -words 49.Op Fl f Ar archive 50.Ek 51.Bk -words 52.Op Fl o Ar options 53.Ar ... 54.Ek 55.Bk -words 56.Op Fl p Ar string 57.Ar ... 58.Ek 59.Bk -words 60.Op Fl s Ar replstr 61.Ar ... 62.Ek 63.Op Fl E Ar limit 64.Bk -words 65.Op Fl U Ar user 66.Ar ... 67.Ek 68.Bk -words 69.Op Fl G Ar group 70.Ar ... 71.Ek 72.Bk -words 73.Oo 74.Fl T 75.Op Ar from_date 76.Op Ar ,to_date 77.Oc 78.Ar ... 79.Ek 80.Op Ar pattern ... 81.Nm pax 82.Fl w 83.Op Fl dituvHLPX 84.Bk -words 85.Op Fl b Ar blocksize 86.Ek 87.Oo 88.Op Fl a 89.Op Fl f Ar archive 90.Oc 91.Bk -words 92.Op Fl x Ar format 93.Ek 94.Bk -words 95.Op Fl s Ar replstr 96.Ar ... 97.Ek 98.Bk -words 99.Op Fl o Ar options 100.Ar ... 101.Ek 102.Bk -words 103.Op Fl U Ar user 104.Ar ... 105.Ek 106.Bk -words 107.Op Fl G Ar group 108.Ar ... 109.Ek 110.Bk -words 111.Op Fl B Ar bytes 112.Ek 113.Bk -words 114.Oo 115.Fl T 116.Op Ar from_date 117.Op Ar ,to_date 118.Op Ar /[c][m] 119.Oc 120.Ar ... 121.Ek 122.Op Ar file ... 123.Nm pax 124.Fl r 125.Fl w 126.Op Fl diklntuvDHLPXYZ 127.Bk -words 128.Op Fl p Ar string 129.Ar ... 130.Ek 131.Bk -words 132.Op Fl s Ar replstr 133.Ar ... 134.Ek 135.Bk -words 136.Op Fl U Ar user 137.Ar ... 138.Ek 139.Bk -words 140.Op Fl G Ar group 141.Ar ... 142.Ek 143.Bk -words 144.Oo 145.Fl T 146.Op Ar from_date 147.Op Ar ,to_date 148.Op Ar /[c][m] 149.Oc 150.Ar ... 151.Ek 152.Op Ar file ... 153.Ar directory 154.Sh DESCRIPTION 155.Nm Pax 156will read, write, and list the members of an archive file, 157and will copy directory hierarchies. 158.Nm Pax 159operation is independent of the specific archive format, 160and supports a wide variety of different archive formats. 161A list of supported archive formats can be found under the description of the 162.Fl x 163option. 164.Pp 165The presence of the 166.Fl r 167and the 168.Fl w 169options specifies which of the following functional modes 170.Nm pax 171will operate under: 172.Em list , read , write , 173and 174.Em copy. 175.Bl -tag -width 6n 176.It <none> 177.Em List . 178.Nm Pax 179will write to 180.Dv standard output 181a table of contents of the members of the archive file read from 182.Dv standard input , 183whose pathnames match the specified 184.Ar patterns. 185The table of contents contains one filename per line 186and is written using single line buffering. 187.It Fl r 188.Em Read . 189.Nm Pax 190extracts the members of the archive file read from the 191.Dv standard input , 192with pathnames matching the specified 193.Ar patterns. 194The archive format and blocking is automatically determined on input. 195When an extracted file is a directory, the entire file hierarchy 196rooted at that directory is extracted. 197All extracted files are created relative to the current file hierarchy. 198The setting of ownership, access and modification times, and file mode of 199the extracted files are discussed in more detail under the 200.Fl p 201option. 202.It Fl w 203.Em Write . 204.Nm Pax 205writes an archive containing the 206.Ar file 207operands to 208.Dv standard output 209using the specified archive format. 210When no 211.Ar file 212operands are specified, a list of files to copy with one per line is read from 213.Dv standard input . 214When a 215.Ar file 216operand is also a directory, the entire file hierarchy rooted 217at that directory will be included. 218.It Fl r Fl w 219.Em Copy . 220.Nm Pax 221copies the 222.Ar file 223operands to the destination 224.Ar directory . 225When no 226.Ar file 227operands are specified, a list of files to copy with one per line is read from 228the 229.Dv standard input . 230When a 231.Ar file 232operand is also a directory the entire file 233hierarchy rooted at that directory will be included. 234The effect of the 235.Em copy 236is as if the copied files were written to an archive file and then 237subsequently extracted, except that there may be hard links between 238the original and the copied files (see the 239.Fl l 240option below). 241.Pp 242.Em Warning : 243The destination 244.Ar directory 245must not be one of the 246.Ar file 247operands or a member of a file hierarchy rooted at one of the 248.Ar file 249operands. 250The result of a 251.Em copy 252under these conditions is unpredictable. 253.El 254.Pp 255While processing a damaged archive during a 256.Em read 257or 258.Em list 259operation, 260.Nm pax 261will attempt to recover from media defects and will search through the archive 262to locate and process the largest number of archive members possible (see the 263.Fl E 264option for more details on error handling). 265.Sh OPERANDS 266.Pp 267The 268.Ar directory 269operand specifies a destination directory pathname. 270If the 271.Ar directory 272operand does not exist, or it is not writable by the user, 273or it is not of type directory, 274.Nm Pax 275will exit with a non-zero exit status. 276.Pp 277The 278.Ar pattern 279operand is used to select one or more pathnames of archive members. 280Archive members are selected using the pattern matching notation described 281by 282.Xr fnmatch 3 . 283When the 284.Ar pattern 285operand is not supplied, all members of the archive will be selected. 286When a 287.Ar pattern 288matches a directory, the entire file hierarchy rooted at that directory will 289be selected. 290When a 291.Ar pattern 292operand does not select at least one archive member, 293.Nm pax 294will write these 295.Ar pattern 296operands in a diagnostic message to 297.Dv standard error 298and then exit with a non-zero exit status. 299.Pp 300The 301.Ar file 302operand specifies the pathname of a file to be copied or archived. 303When a 304.Ar file 305operand does not select at least one archive member, 306.Nm pax 307will write these 308.Ar file 309operand pathnames in a diagnostic message to 310.Dv standard error 311and then exit with a non-zero exit status. 312.Sh OPTIONS 313.Pp 314The following options are supported: 315.Bl -tag -width 4n 316.It Fl r 317Read an archive file from 318.Dv standard input 319and extract the specified 320.Ar files . 321If any intermediate directories are needed in order to extract an archive 322member, these directories will be created as if 323.Xr mkdir 2 324was called with the bitwise inclusive 325.Dv OR 326of 327.Dv S_IRWXU , S_IRWXG , 328and 329.Dv S_IRWXO 330as the mode argument. 331When the selected archive format supports the specification of linked 332files and these files cannot be linked while the archive is being extracted, 333.Nm pax 334will write a diagnostic message to 335.Dv standard error 336and exit with a non-zero exit status at the completion of operation. 337.It Fl w 338Write files to the 339.Dv standard output 340in the specified archive format. 341When no 342.Ar file 343operands are specified, 344.Dv standard input 345is read for a list of pathnames with one per line without any leading or 346trailing 347.Aq blanks . 348.It Fl a 349Append 350.Ar files 351to the end of an archive that was previously written. 352If an archive format is not specified with a 353.Fl x 354option, the format currently being used in the archive will be selected. 355Any attempt to append to an archive in a format different from the 356format already used in the archive will cause 357.Nm pax 358to exit immediately 359with a non-zero exit status. 360The blocking size used in the archive volume where writing starts 361will continue to be used for the remainder of that archive volume. 362.Pp 363.Em Warning : 364Many storage devices are not able to support the operations necessary 365to perform an append operation. 366Any attempt to append to an archive stored on such a device may damage the 367archive or have other unpredictable results. 368Tape drives in particular are more likely to not support an append operation. 369An archive stored in a regular file system file or on a disk device will 370usually support an append operation. 371.It Fl b Ar blocksize 372When 373.Em writing 374an archive, 375block the output at a positive decimal integer number of 376bytes per write to the archive file. 377The 378.Ar blocksize 379must be a multiple of 512 bytes with a maximum of 32256 bytes. 380A 381.Ar blocksize 382can end with 383.Li k 384or 385.Li b 386to specify multiplication by 1024 (1K) or 512, respectively. 387A pair of 388.Ar blocksizes 389can be separated by 390.Li x 391to indicate a product. 392A specific archive device may impose additional restrictions on the size 393of blocking it will support. 394When blocking is not specified, the default 395.Ar blocksize 396is dependent on the specific archive format being used (see the 397.Fl x 398option). 399.It Fl c 400Match all file or archive members 401.Em except 402those specified by the 403.Ar pattern 404and 405.Ar file 406operands. 407.It Fl d 408Cause files of type directory being copied or archived, or archive members of 409type directory being extracted, to match only the directory file or archive 410member and not the file hierarchy rooted at the directory. 411.It Fl f Ar archive 412Specify 413.Ar archive 414as the pathname of the input or output archive, overriding the default 415.Dv standard input 416(for 417.Em list 418and 419.Em read ) 420or 421.Dv standard output 422(for 423.Em write ) . 424A single archive may span multiple files and different archive devices. 425When required, 426.Nm pax 427will prompt for the pathname of the file or device of the next volume in the 428archive. 429.It Fl i 430Interactively rename files or archive members. 431For each archive member matching a 432.Ar pattern 433operand or each file matching a 434.Ar file 435operand, 436.Nm pax 437will prompt to 438.Pa /dev/tty 439giving the name of the file, its file mode and its modification time. 440.Nm Pax 441will then read a line from 442.Pa /dev/tty . 443If this line is blank, the file or archive member is skipped. 444If this line consists of a single period, the 445file or archive member is processed with no modification to its name. 446Otherwise, its name is replaced with the contents of the line. 447.Nm Pax 448will immediately exit with a non-zero exit status if 449.Dv <EOF> 450is encountered when reading a response or if 451.Pa /dev/tty 452cannot be opened for reading and writing. 453.It Fl k 454Do not overwrite existing files. 455.It Fl l 456Link files. (The letter ell). 457In the 458.Em copy 459mode ( 460.Fl r 461.Fl w ) , 462hard links are made between the source and destination file hierarchies 463whenever possible. 464.It Fl n 465Select the first archive member that matches each 466.Ar pattern 467operand. 468No more than one archive member is matched for each 469.Ar pattern . 470When members of type directory are matched, the file hierarchy rooted at that 471directory is also matched (unless 472.Fl d 473is also specified). 474.It Fl o Ar options 475Information to modify the algorithm for extracting or writing archive files 476which is specific to the archive format specified by 477.Fl x . 478In general, 479.Ar options 480take the form: 481.Cm name=value 482.It Fl p Ar string 483Specify one or more file characteristic options (privileges). 484The 485.Ar string 486option-argument is a string specifying file characteristics to be retained or 487discarded on extraction. 488The string consists of the specification characters 489.Cm a , e , m , o , 490and 491.Cm p . 492Multiple characteristics can be concatenated within the same string 493and multiple 494.Fl p 495options can be specified. 496The meaning of the specification characters are as follows: 497.Bl -tag -width 2n 498.It Cm a 499Do not preserve file access times. 500By default, file access times are preserved whenever possible. 501.It Cm e 502.Sq Preserve everything , 503the user ID, group ID, file mode bits, 504file access time, and file modification time. 505This is intended to be used by 506.Em root , 507someone with all the appropriate privileges, in order to preserve all 508aspects of the files as they are recorded in the archive. 509The 510.Cm e 511flag is the sum of the 512.Cm o 513and 514.Cm p 515flags. 516.It Cm m 517Do not preserve file modification times. 518By default, file modification times are preserved whenever possible. 519.It Cm o 520Preserve the user ID and group ID. 521.It Cm p 522.Sq Preserve 523the file mode bits. 524This intended to be used by a 525.Em user 526with regular privileges who wants to preserve all aspects of the file other 527than the ownership. 528The file times are preserved by default, but two other flags are offered to 529disable this and use the time of extraction instead. 530.El 531.Pp 532In the preceding list, 533.Sq preserve 534indicates that an attribute stored in the archive is given to the 535extracted file, subject to the permissions of the invoking 536process. 537Otherwise the attribute of the extracted file is determined as 538part of the normal file creation action. 539If neither the 540.Cm e 541nor the 542.Cm o 543specification character is specified, or the user ID and group ID are not 544preserved for any reason, 545.Nm pax 546will not set the 547.Dv S_ISUID 548.Em ( setuid ) 549and 550.Dv S_ISGID 551.Em ( setgid ) 552bits of the file mode. 553If the preservation of any of these items fails for any reason, 554.Nm pax 555will write a diagnostic message to 556.Dv standard error . 557Failure to preserve these items will affect the final exit status, 558but will not cause the extracted file to be deleted. 559If the file characteristic letters in any of the string option-arguments are 560duplicated or conflict with each other, the one(s) given last will take 561precedence. 562For example, if 563.Dl Fl p Ar eme 564is specified, file modification times are still preserved. 565.It Fl s Ar replstr 566Modify the file or archive member names specified by the 567.Ar pattern 568or 569.Ar file 570operands according to the substitution expression 571.Ar replstr , 572using the syntax of the 573.Xr ed 1 574utility regular expressions. 575The format of these regular expressions are: 576.Dl /old/new/[gp] 577As in 578.Xr ed 1 , 579.Cm old 580is a basic regular expression and 581.Cm new 582can contain an ampersand (&), \\n (where n is a digit) back-references, 583or subexpression matching. 584The 585.Cm old 586string may also contain 587.Dv <newline> 588characters. 589Any non-null character can be used as a delimiter (/ is shown here). 590Multiple 591.Fl s 592expressions can be specified. 593The expressions are applied in the order they are specified on the 594command line, terminating with the first successful substitution. 595The optional trailing 596.Cm g 597continues to apply the substitution expression to the pathname substring 598which starts with the first character following the end of the last successful 599substitution. The 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 <original pathname> >> <new pathname> 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 pax 613to be the same as they were before being read or accessed by 614.Nm pax . 615.It Fl u 616Ignore files that are older (having a less recent file modification time) 617than a pre-existing file or archive member with the same name. 618During 619.Em read , 620an archive member with the same name as a file in the file system will be 621extracted if the archive member is newer than the file. 622During 623.Em write , 624a file system member with the same name as an archive member will be 625written to the archive if it is newer than the archive member. 626During 627.Em copy , 628the file in the destination hierarchy is replaced by the file in the source 629hierarchy or by a link to the file in the source hierarchy if the file in 630the source hierarchy is newer. 631.It Fl v 632During a 633.Em list 634operation, produce a verbose table of contents using the format of the 635.Xr ls 1 636utility with the 637.Fl l 638option. 639For pathnames representing a hard link to a previous member of the archive, 640the output has the format: 641.Dl <ls -l listing> == <link name> 642For pathnames representing a symbolic link, the output has the format: 643.Dl <ls -l listing> => <link name> 644Where <ls -l listing> is the output format specified by the 645.Xr ls 1 646utility when used with the 647.Fl l 648option. 649Otherwise for all the other operational modes ( 650.Em read , write , 651and 652.Em copy ) , 653pathnames are written and flushed to 654.Dv standard error 655without a trailing 656.Dv <newline> 657as soon as processing begins on that file or 658archive member. 659The trailing 660.Dv <newline> , 661is not buffered, and is written only after the file has been read or written. 662.It Fl x Ar format 663Specify the output archive format, with the default format being 664.Ar ustar . 665.Nm Pax 666currently supports the following formats: 667.Bl -tag -width "sv4cpio" 668.It Ar cpio 669The extended cpio interchange format specified in the 670.St -p1003.2 671standard. 672The default blocksize for this format is 5120 bytes. 673Inode and device information about a file (used for detecting file hard links 674by this format) which may be truncated by this format is detected by 675.Nm pax 676and is repaired. 677.It Ar bcpio 678The old binary cpio format. 679The default blocksize for this format is 5120 bytes. 680This format is not very portable and should not be used when other formats 681are available. 682Inode and device information about a file (used for detecting file hard links 683by this format) which may be truncated by this format is detected by 684.Nm pax 685and is repaired. 686.It Ar sv4cpio 687The System V release 4 cpio. 688The default blocksize for this format is 5120 bytes. 689Inode and device information about a file (used for detecting file hard links 690by this format) which may be truncated by this format is detected by 691.Nm pax 692and is repaired. 693.It Ar sv4crc 694The System V release 4 cpio with file crc checksums. 695The default blocksize for this format is 5120 bytes. 696Inode and device information about a file (used for detecting file hard links 697by this format) which may be truncated by this format is detected by 698.Nm pax 699and is repaired. 700.It Ar tar 701The old BSD tar format as found in BSD4.3. 702The default blocksize for this format is 10240 bytes. 703Pathnames stored by this format must be 100 characters or less in length. 704Only 705.Em regular 706files, 707.Em hard links , soft links , 708and 709.Em directories 710will be archived (other file system types are not supported). 711For backwards compatibility with even older tar formats, a 712.Fl o 713option can be used when writing an archive to omit the storage of directories. 714This option takes the form: 715.Dl Fl o Cm write_opt=nodir 716.It Ar ustar 717The extended tar interchange format specified in the 718.St -p1003.2 719standard. 720The default blocksize for this format is 10240 bytes. 721Pathnames stored by this format must be 250 characters or less in length. 722.El 723.Pp 724.Nm Pax 725will detect and report any file that it is unable to store or extract 726as the result of any specific archive format restrictions. 727The individual archive formats may impose additional restrictions on use. 728Typical archive format restrictions include (but are not limited to): 729file pathname length, file size, link pathname length and the type of the file. 730.It Fl B Ar bytes 731Limit the number of bytes written to a single archive volume to 732.Ar bytes . 733The 734.Ar bytes 735limit can end with 736.Li m , 737.Li k , 738or 739.Li b 740to specify multiplication by 1048576 (1M), 1024 (1K) or 512, respectively. 741A pair of 742.Ar bytes 743limits can be separated by 744.Li x 745to indicate a product. 746.Pp 747.Em Warning : 748Only use this option when writing an archive to a device which supports 749an end of file read condition based on last (or largest) write offset 750(such as a regular file or a tape drive). 751The use of this option with a floppy or hard disk is not recommended. 752.It Fl D 753This option is the same as the 754.Fl u 755option, except that the file inode change time is checked instead of the 756file modification time. 757The file inode change time can be used to select files whose inode information 758(e.g. uid, gid, etc.) is newer than a copy of the file in the destination 759.Ar directory . 760.It Fl E Ar limit 761Limit the number of consecutive read faults while trying to read a flawed 762archives to 763.Ar limit . 764With a positive 765.Ar limit , 766.Nm pax 767will attempt to recover from an archive read error and will 768continue processing starting with the next file stored in the archive. 769A 770.Ar limit 771of 0 will cause 772.Nm pax 773to stop operation after the first read error is detected on an archive volume. 774A 775.Ar limit 776of 777.Li NONE 778will cause 779.Nm pax 780to attempt to recover from read errors forever. 781The default 782.Ar limit 783is a small positive number of retries. 784.Pp 785.Em Warning: 786Using this option with 787.Li NONE 788should be used with extreme caution as 789.Nm pax 790may get stuck in an infinite loop on a very badly flawed archive. 791.It Fl G Ar group 792Select a file based on its 793.Ar group 794name, or when starting with a 795.Cm # , 796a numeric gid. 797A '\\' can be used to escape the 798.Cm # . 799Multiple 800.Fl G 801options may be supplied and checking stops with the first match. 802.It Fl H 803Follow only command line symbolic links while performing a physical file 804system traversal. 805.It Fl L 806Follow all symbolic links to perform a logical file system traversal. 807.It Fl P 808Do not follow symbolic links, perform a physical file system traversal. 809This is the default mode. 810.It Fl T Ar [from_date][,to_date][/[c][m]] 811Allow files to be selected based on a file modification or inode change 812time falling within a specified time range of 813.Ar from_date 814to 815.Ar to_date 816(the dates are inclusive). 817If only a 818.Ar from_date 819is supplied, all files with a modification or inode change time 820equal to or younger are selected. 821If only a 822.Ar to_date 823is supplied, all files with a modification or inode change time 824equal to or older will be selected. 825When the 826.Ar from_date 827is equal to the 828.Ar to_date , 829only files with a modification or inode change time of exactly that 830time will be selected. 831.Pp 832When 833.Nm pax 834is in the 835.Em write 836or 837.Em copy 838mode, the optional trailing field 839.Ar [c][m] 840can be used to determine which file time (inode change, file modification or 841both) are used in the comparison. 842If neither is specified, the default is to use file modification time only. 843The 844.Ar m 845specifies the comparison of file modification time (the time when 846the file was last written). 847The 848.Ar c 849specifies the comparison of inode change time (the time when the file 850inode was last changed; e.g. a change of owner, group, mode, etc). 851When 852.Ar c 853and 854.Ar m 855are both specified, then the modification and inode change times are 856both compared. 857The inode change time comparison is useful in selecting files whose 858attributes were recently changed or selecting files which were recently 859created and had their modification time reset to an older time (as what 860happens when a file is extracted from an archive and the modification time 861is preserved). 862Time comparisons using both file times is useful when 863.Nm pax 864is used to create a time based incremental archive (only files that were 865changed during a specified time range will be archived). 866.Pp 867A time range is made up of six different fields and each field must contain two 868digits. 869The format is: 870.Dl [yy[mm[dd[hh]]]]mm[.ss] 871Where 872.Cm yy 873is the last two digits of the year, 874the first 875.Cm mm 876is the month (from 01 to 12), 877.Cm dd 878is the day of the month (from 01 to 31), 879.Cm hh 880is the hour of the day (from 00 to 23), 881the second 882.Cm mm 883is the minute (from 00 to 59), 884and 885.Cm ss 886is the seconds (from 00 to 59). 887The minute field 888.Cm mm 889is required, while the other fields are optional and must be added in the 890following order: 891.Dl Cm hh , dd , mm , yy . 892The 893.Cm ss 894field may be added independently of the other fields. 895Time ranges are relative to the current time, so 896.Dl Fl T Ar 1234/cm 897would select all files with a modification or inode change time 898of 12:34 PM today or later. 899Multiple 900.Fl T 901time range can be supplied and checking stops with the first match. 902.It Fl U Ar user 903Select a file based on its 904.Ar user 905name, or when starting with a 906.Cm # , 907a numeric uid. 908A '\\' can be used to escape the 909.Cm # . 910Multiple 911.Fl U 912options may be supplied and checking stops with the first match. 913.It Fl X 914When traversing the file hierarchy specified by a pathname, 915do not descend into directories that have a different device ID. 916See the 917.Li st_dev 918field as described in 919.Xr stat 2 920for more information about device ID's. 921.It Fl Y 922This option is the same as the 923.Fl D 924option, except that the inode change time is checked using the 925pathname created after all the file name modifications have completed. 926.It Fl Z 927This option is the same as the 928.Fl u 929option, except that the modification time is checked using the 930pathname created after all the file name modifications have completed. 931.El 932.Pp 933The options that operate on the names of files or archive members ( 934.Fl c , 935.Fl i , 936.Fl n , 937.Fl s , 938.Fl u , 939.Fl v , 940.Fl D , 941.Fl G , 942.Fl T , 943.Fl U , 944.Fl Y , 945and 946.Fl Z ) 947interact as follows. 948.Pp 949When extracting files during a 950.Em read 951operation, archive members are 952.Sq selected , 953based only on the user specified pattern operands as modified by the 954.Fl c , 955.Fl n , 956.Fl u , 957.Fl D , 958.Fl G , 959.Fl T , 960.Fl U 961options. 962Then any 963.Fl s 964and 965.Fl i 966options will modify in that order, the names of these selected files. 967Then the 968.Fl Y 969and 970.Fl Z 971options will be applied based on the final pathname. 972Finally the 973.Fl v 974option will write the names resulting from these modifications. 975.Pp 976When archiving files during a 977.Em write 978operation, or copying files during a 979.Em copy 980operation, archive members are 981.Sq selected , 982based only on the user specified pathnames as modified by the 983.Fl n , 984.Fl u , 985.Fl D , 986.Fl G , 987.Fl T , 988and 989.Fl U 990options (the 991.Fl D 992option only applies during a copy operation). 993Then any 994.Fl s 995and 996.Fl i 997options will modify in that order, the names of these selected files. 998Then during a 999.Em copy 1000operation the 1001.Fl Y 1002and the 1003.Fl Z 1004options will be applied based on the final pathname. 1005Finally the 1006.Fl v 1007option will write the names resulting from these modifications. 1008.Pp 1009When one or both of the 1010.Fl u 1011or 1012.Fl D 1013options are specified along with the 1014.Fl n 1015option, a file is not considered selected unless it is newer 1016than the file to which it is compared. 1017.Sh EXAMPLES 1018The command: 1019.Dl pax -w -f /dev/rst0 .\ 1020copies the contents of the current directory to the device 1021.Pa /dev/rst0 . 1022.Pp 1023The command: 1024.Dl pax -r -v -f filename 1025gives the verbose table of contents for an archive stored in 1026.Pa filename . 1027.Pp 1028The following commands: 1029.Dl mkdir newdir 1030.Dl cd olddir 1031.Dl pax -rw .\ newdir 1032will copy the entire 1033.Pa olddir 1034directory hierarchy to 1035.Pa newdir . 1036.Pp 1037The command: 1038.Dl pax -r -s ',^//*usr//*,,' -f a.pax 1039reads the archive 1040.Pa a.pax , 1041with all files rooted in ``/usr'' into the archive extracted relative to the 1042current directory. 1043.Pp 1044The command: 1045.Dl pax -rw -i .\ dest_dir 1046can be used to interactively select the files to copy from the current 1047directory to 1048.Pa dest_dir . 1049.Pp 1050The command: 1051.Dl pax -r -pe -U root -G bin -f a.pax 1052will extract all files from the archive 1053.Pa a.pax 1054which are owned by 1055.Em root 1056with group 1057.Em bin 1058and will preserve all file permissions. 1059.Pp 1060The command: 1061.Dl pax -r -w -v -Y -Z home /backup 1062will update (and list) only those files in the destination directory 1063.Pa /backup 1064which are older (less recent inode change or file modification times) than 1065files with the same name found in the source file tree 1066.Pa home . 1067.Sh STANDARDS 1068The 1069.Nm pax 1070utility is a superset of the 1071.St -p1003.2 1072standard. 1073The options 1074.Fl B , 1075.Fl D , 1076.Fl E , 1077.Fl G , 1078.Fl H , 1079.Fl L , 1080.Fl P , 1081.Fl T , 1082.Fl U , 1083.Fl Y , 1084.Fl Z , 1085the archive formats 1086.Ar bcpio , 1087.Ar sv4cpio , 1088.Ar sv4crc , 1089.Ar tar , 1090and the flawed archive handling during 1091.Ar list 1092and 1093.Ar read 1094operations are extensions to the 1095.Tn POSIX 1096standard. 1097.Sh AUTHOR 1098Keith Muller at the University of California, San Diego 1099.Sh ERRORS 1100.Nm pax 1101will exit with one of the following values: 1102.Bl -tag -width 2n 1103.It 0 1104All files were processed successfully. 1105.It 1 1106An error occurred. 1107.El 1108.Pp 1109Whenever 1110.Nm pax 1111cannot create a file or a link when reading an archive or cannot 1112find a file when writing an archive, or cannot preserve the user ID, 1113group ID, or file mode when the 1114.Fl p 1115option is specified, a diagnostic message is written to 1116.Dv standard error 1117and a non-zero exit status will be returned, but processing will continue. 1118In the case where pax cannot create a link to a file, 1119.Nm pax 1120will not create a second copy of the file. 1121.Pp 1122If the extraction of a file from an archive is prematurely terminated by 1123a signal or error, 1124.Nm pax 1125may have only partially extracted a file the user wanted. 1126Additionally, the file modes of extracted files and directories 1127may have incorrect file bits, and the modification and access times may be 1128wrong. 1129.Pp 1130If the creation of an archive is prematurely terminated by a signal or error, 1131.Nm pax 1132may have only partially created the archive which may violate the specific 1133archive format specification. 1134.Pp 1135If while doing a 1136.Em copy , 1137.Nm pax 1138detects a file is about to overwrite itself, the file is not copied, 1139a diagnostic message is written to 1140.Dv standard error 1141and when 1142.Nm pax 1143completes it will exit with a non-zero exit status. 1144