1.\" Copyright (c) 1992 Keith Muller. 2.\" Copyright (c) 1992 The Regents of the University of California. 3.\" 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 1.2 (Berkeley) 01/14/93 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 dituvHLX 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 diklntuvDHLXYZ 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 159supports a wide variety of different archive formats. 160These archive formats are described in more detail under the 161.Fl x 162option. 163.Pp 164The operand 165.Ar directory 166specifies a destination directory pathname. 167.Nm Pax 168will exit with a non-zero exit status 169if the 170.Ar directory 171operand does not exist, or it is not writable by the user, 172or it is not of type directory. 173.Pp 174The operand 175.Ar pattern 176is used to select one or more pathnames of archive members using the pattern 177matching notation described by 178.Xr fnmatch 3 . 179When no 180.Ar patterns 181are specified, all members of the archive will be selected. 182When a 183.Ar pattern 184matches a directory, the entire file hierarchy rooted at that directory will 185be selected. 186If at the completion of operation a 187.Ar pattern 188operand did not select at least one archive member, 189.Nm pax 190will write these 191.Ar pattern 192operands in a diagnostic message to 193.Dv standard error 194and then exit with a non-zero exit status. 195.Pp 196The operand 197.Ar file 198specifies the pathname of a file to be copied or archived. 199If at the completion of operation a 200.Ar file 201operand did not select at least one archived file, 202.Nm pax 203will write these 204.Ar file 205operand pathnames in a diagnostic message to 206.Dv standard error 207and then exit with a non-zero exit status. 208.Pp 209.Nm Pax 210operates in one of four operational modes based on the presence of 211the 212.Fl r 213and the 214.Fl w 215options. 216These operational modes are: 217.Em list , read , write , 218and 219.Em copy. 220.Bl -tag -width 6n 221.It <none> 222.Em List . 223.Nm Pax 224will write to 225.Dv standard output 226a table of contents of the members of the 227archive file read from 228.Dv standard input , 229whose pathnames match the specified 230.Ar patterns. 231The table of contents is written with one filename per line and is not buffered 232more than a single line at a time. 233.It Fl r 234.Em Read . 235.Nm Pax 236extracts the members of the archive file read from the 237.Dv standard input , 238with pathnames matching the specified 239.Ar patterns. 240The format and the blocking of the archive is automatically determined on 241input. 242When an extracted file is a directory, the entire file hierarchy 243rooted at that directory is extracted. 244All extracted files are created relative to the current file hierarchy. 245The ownership, access and modification times, and file mode of 246the extracted files are discussed in more detail under the 247.Fl p 248option. 249.It Fl w 250.Em Write . 251.Nm Pax 252writes an archive containing the 253.Ar file 254operands to 255.Dv standard output 256using the specified archive format. 257When no 258.Ar file 259operands are specified, a list of files to copy, one per line, is read from 260.Dv standard input . 261A 262.Ar file 263operand that is also a directory will include the entire file hierarchy rooted 264at that directory. 265.It Fl r Fl w 266.Em Copy . 267.Nm Pax 268copies the 269.Ar file 270operands to the destination 271.Ar directory . 272When no 273.Ar file 274operands are specified, a list of files to copy, one per line, is read from 275the 276.Dv standard input . 277A 278.Ar file 279operand that is also a directory will include the entire file 280hierarchy rooted at that directory. 281The effect of the 282.Em copy 283is as if the copied files were 284written to an archive file and then subsequently extracted, 285except that there may be hard links between the original and the 286copied files (see the 287.Fl l 288option below). 289.Pp 290.Em Warning : 291The destination 292.Ar directory 293must not be one of the 294.Ar file 295operands or a member of a file hierarchy rooted at one of the 296.Ar file 297operands. 298The result of a 299.Em copy 300under these conditions is unpredictable. 301.El 302.Pp 303While processing a damaged archive during a 304.Em read 305or 306.Em list 307operation, 308.Nm pax 309will attempt to recover from media defects and will search through the archive 310to locate and process the largest number of archive members possible (see the 311.Fl E 312option for more details on error handling). 313.Sh OPTIONS 314.Pp 315The following options are supported: 316.Bl -tag -width 4n 317.It Fl r 318Read an archive file from 319.Dv standard input 320and extract the specified 321.Ar files . 322If any intermediate directories are needed in order to extract an archive 323member, these directories will be created as if 324.Xr mkdir 2 325was called with the bitwise inclusive 326.Dv OR 327of 328.Dv S_IRWXU , S_IRWXG , 329and 330.Dv S_IRWXO 331as the mode argument. 332When the selected archive format supports the specification of linked 333files and these files cannot be linked while the archive is being extracted, 334.Nm pax 335will write a diagnostic message to 336.Dv standard error 337and exit with a non-zero exit status at the completion of operation. 338.It Fl w 339Write files to the 340.Dv standard output 341in the specified archive format. 342When no 343.Ar file 344operands are specified, 345.Dv standard input 346is read for a list of pathnames, one per line, without any leading or trailing 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, 395the default 396.Ar blocksize 397is dependent on the specific archive format being used (see the 398.Fl x 399option). 400.It Fl c 401Match all file or archive members 402.Em except 403those specified by the 404.Ar pattern 405and 406.Ar file 407operands. 408.It Fl d 409Cause files of type directory being copied or archived, or archive members of 410type directory being extracted, to match only the directory file or archive 411member and not the file hierarchy rooted at the directory. 412.It Fl f Ar archive 413Specify 414.Ar archive 415as the pathname of the input or output archive, overriding the default 416.Dv standard input 417(for 418.Em list 419and 420.Em read ) 421or 422.Dv standard output 423(for 424.Em write ) . 425A single archive may span multiple files and different archive devices. 426When required, 427.Nm pax 428will prompt for the pathname of the file or device of the next volume in the 429archive. 430.It Fl i 431Interactively rename files or archive members. 432For each archive member matching a 433.Ar pattern 434operand or each file matching a 435.Ar file 436operand, 437.Nm pax 438will prompt to 439.Pa /dev/tty 440giving the name of the file, its file mode and its modification time. 441.Nm Pax 442will then read a line from 443.Pa /dev/tty . 444If this line is blank, the file or archive member is skipped. 445If this line consists of a single period, the 446file or archive member is processed with no modification to its name. 447Otherwise, its name is replaced with the contents of the line. 448.Nm Pax 449will immediately exit with a non-zero exit status if 450.Dv <EOF> 451is encountered when reading a response or if 452.Pa /dev/tty 453cannot be opened for reading and writing. 454.It Fl k 455Do not overwrite existing files. 456.It Fl l 457Link files. (The letter ell). 458In the 459.Em copy 460mode ( 461.Fl r 462.Fl w ) , 463hard links are made between the source and destination file hierarchies 464whenever possible. 465.It Fl n 466Select the first archive member that matches each 467.Ar pattern 468operand. 469No more than one archive member is matched for each 470.Ar pattern . 471When members of type directory are matched, the file hierarchy rooted at that 472directory is also matched (unless 473.Fl d 474is also specified). 475.It Fl o Ar options 476Information to modify the algorithm for extracting or writing archive files 477which is specific to the archive format specified by 478.Fl x . 479In general, 480.Ar options 481take the form: 482.Cm name=value 483.It Fl p Ar string 484Specify one or more file characteristic options (privileges). 485The 486.Ar string 487option-argument is a string specifying file characteristics to be retained or 488discarded on extraction. 489The string consists of the specification characters 490.Cm a , e , m , o , 491and 492.Cm p . 493Multiple characteristics can be concatenated within the same string 494and multiple 495.Fl p 496options can be specified. 497The meaning of the specification characters are as follows: 498.Bl -tag -width 2n 499.It Cm a 500Do not preserve file access times. 501By default, file access times are preserved whenever possible. 502.It Cm e 503.Sq Preserve everything , 504the user ID, group ID, file mode bits, 505file access time, and file modification time. 506This is intended to be used by 507.Em root , 508someone with all the appropriate privileges, in order to preserve all 509aspects of the files as they are recorded in the archive. 510The 511.Cm e 512flag is the sum of the 513.Cm o 514and 515.Cm p 516flags. 517.It Cm m 518Do not preserve file modification times. 519By default, file modification times are preserved whenever possible. 520.It Cm o 521Preserve the user ID and group ID. 522.It Cm p 523.Sq Preserve 524the file mode bits. 525This intended to be used by a 526.Em user 527with regular privileges who wants to preserve all aspects of the file other 528than the ownership. 529The file times are preserved by default, but two other flags are offered to 530disable this and use the time of extraction instead. 531.El 532.Pp 533In the preceding list, 534.Sq preserve 535indicates that an attribute stored in the archive is given to the 536extracted file, subject to the permissions of the invoking 537process. 538Otherwise the attribute of the extracted file is determined as 539part of the normal file creation action. 540If neither the 541.Cm e 542nor the 543.Cm o 544specification character is specified, or the user ID and group ID are not 545preserved for any reason, 546.Nm pax 547will not set the 548.Dv S_ISUID 549.Em ( setuid ) 550and 551.Dv S_ISGID 552.Em ( setgid ) 553bits of the file mode. 554If the preservation of any of these items fails for any reason, 555.Nm pax 556will write a diagnostic message to 557.Dv standard error . 558Failure to preserve these items will affect the final exit status, 559but will not cause the extracted file to be deleted. 560If the file characteristic letters in any of the string option-arguments are 561duplicated or conflict with each other, the one(s) given last will take 562precedence. 563For example, if 564.Dl Fl p Ar eme 565is specified, file modification times are still preserved. 566.It Fl s Ar replstr 567Modify the file or archive member names specified by the 568.Ar pattern 569or 570.Ar file 571operands according to the substitution expression 572.Ar replstr , 573using the syntax of the 574.Xr ed 1 575utility regular expressions. 576The format of these regular expressions are: 577.Dl /old/new/[gp] 578As in 579.Xr ed 1 , 580.Cm old 581is a basic regular expression and 582.Cm new 583can contain an ampersand (&), \\n (where n is a digit) back-references, 584or subexpression matching. 585The 586.Cm old 587string may also contain 588.Dv <newline> 589characters. 590Any non-null character can be used as a delimiter (/ is shown here). 591Multiple 592.Fl s 593expressions can be specified. 594The expressions are applied in the order they are specified on the 595command line, terminating with the first successful substitution. 596The optional trailing 597.Cm g 598continues to apply the substitution expression to the pathname substring 599which starts with the first character following the end of the last successful 600substitution. The first unsuccessful substitution stops the operation of the 601.Cm g 602option. 603The optional trailing 604.Cm p 605will cause the final result of a successful substitution to be written to 606.Dv standard error 607in the following format: 608.Dl <original pathname> >> <new pathname> 609File or archive member names that substitute to the empty string 610are not selected and will be skipped. 611.It Fl t 612Reset the access times of any file or directory read or accessed by 613.Nm pax 614to be the same as they were before being read or accessed by 615.Nm pax . 616.It Fl u 617Ignore files that are older (having a less recent file modification time) 618than a pre-existing file or archive member with the same name. 619During 620.Em read , 621an archive member with the same name as a file in the file system will be 622extracted if the archive member is newer than the file. 623During 624.Em write , 625a file system member with the same name as an archive member will be 626written to the archive if it is newer than the archive member. 627During 628.Em copy , 629the file in the destination hierarchy is replaced by the file in the source 630hierarchy or by a link to the file in the source hierarchy if the file in 631the source hierarchy is newer. 632.It Fl v 633During a 634.Em list 635operation, produce a verbose table of contents using the format of the 636.Xr ls 1 637utility with the 638.Fl l 639option. 640For pathnames representing a hard link to a previous member of the archive, 641the output has the format: 642.Dl <ls -l listing> == <link name> 643For pathnames representing a symbolic link, the output has the format: 644.Dl <ls -l listing> => <link name> 645Where <ls -l listing> is the output format specified by the 646.Xr ls 1 647utility when used with the 648.Fl l 649option. 650Otherwise for all the other operational modes ( 651.Em read , write , 652and 653.Em copy ) , 654pathnames are written and flushed to 655.Dv standard error 656without a trailing 657.Dv <newline> 658as soon as processing begins on that file or 659archive member. 660The trailing 661.Dv <newline> , 662is not buffered, and is written only after the file has been read or written. 663.It Fl x Ar format 664Specify the output archive format, with the default format being 665.Ar ustar . 666.Nm Pax 667currently supports the following formats: 668.Bl -tag -width "sv4cpio" 669.It Ar cpio 670The extended cpio interchange format specified in the 671.St -p1003.2 672standard. 673The default blocksize for this format is 5120 bytes. 674Inode and device information about a file (used for detecting file hard links 675by this format) which may be truncated by this format is detected by 676.Nm pax 677and is repaired. 678.It Ar bcpio 679The old binary cpio format. 680The default blocksize for this format is 5120 bytes. 681This format is not very portable and should not be used when other formats 682are available. 683Inode and device information about a file (used for detecting file hard links 684by this format) which may be truncated by this format is detected by 685.Nm pax 686and is repaired. 687.It Ar sv4cpio 688The System V release 4 cpio. 689The default blocksize for this format is 5120 bytes. 690Inode and device information about a file (used for detecting file hard links 691by this format) which may be truncated by this format is detected by 692.Nm pax 693and is repaired. 694.It Ar sv4crc 695The System V release 4 cpio with file crc checksums. 696The default blocksize for this format is 5120 bytes. 697Inode and device information about a file (used for detecting file hard links 698by this format) which may be truncated by this format is detected by 699.Nm pax 700and is repaired. 701.It Ar tar 702The old BSD tar format as found in BSD4.3. 703The default blocksize for this format is 10240 bytes. 704Pathnames stored by this format must be 100 characters or less in length. 705Only 706.Em regular 707files, 708.Em hard links , soft links , 709and 710.Em directories 711will be archived (other file system types are not supported). 712For backwards compatability with even older tar formats, a 713.Fl o 714option can be used when writing an archive to omit the storage of directories. 715This option takes the form: 716.Dl Fl o Cm write_opt=nodir 717.It Ar ustar 718The extended tar interchange format specified in the 719.St -p1003.2 720standard. 721The default blocksize for this format is 10240 bytes. 722Pathnames stored by this format must be 250 characters or less in length. 723.El 724.Pp 725.Nm Pax 726will detect and report any file that it is unable to store or extract 727as the result of any specific archive format restrictions. 728The individual archive formats may impose additional restrictions on use. 729Typical archive format restrictions include (but are not limited to): 730file pathname length, file size, link pathname length and the type of the file. 731.It Fl B Ar bytes 732Limit the number of bytes written to a single archive volume to 733.Ar bytes . 734The 735.Ar bytes 736limit can end with 737.Li m , 738.Li k , 739or 740.Li b 741to specify multiplication by 1048576 (1M), 1024 (1K) or 512, respectively. 742A pair of 743.Ar bytes 744limits can be separated by 745.Li x 746to indicate a product. 747.Pp 748.Em Warning : 749Only use this option when writing a archive to a device which supports 750an end of file read condition based on last (or largest) write offset 751(such as a regular file or a tape drive). 752The use of this option with a floppy or hard disk is not recommended. 753.It Fl D 754This option is the same as the 755.Fl u 756option, except that the file inode change time is checked instead of the 757file modification time. 758The file inode change time can be used to select files whose inode information 759(e.g. uid, gid, etc.) is newer than a copy of the file in the destination 760.Ar directory . 761.It Fl E Ar limit 762Limit the number of consecutive read faults while trying to read a flawed 763archives to 764.Ar limit . 765With a positive 766.Ar limit , 767.Nm pax 768will attempt to recover from an archive read error and will 769continue processing starting with the next file stored in the archive. 770A 771.Ar limit 772of 0 will cause 773.Nm pax 774to stop operation after the first read error is detected on an archive volume. 775A 776.Ar limit 777of 778.Li NONE 779will cause 780.Nm pax 781to attempt to recover from read errors forever. 782The default 783.Ar limit 784is a small positive number of retries. 785.Pp 786.Em Warning: 787Using this option with 788.Li NONE 789should be used with extreme caution as 790.Nm pax 791may get stuck in an infinite loop on a very badly flawed archive. 792.It Fl G Ar group 793Select a file based on its 794.Ar group 795name, or when starting with a 796.Cm # , 797a numeric gid. 798A '\\' can be used to escape the 799.Cm # . 800Multiple 801.Fl G 802options may be supplied and checking stops with the first match. 803.It Fl H 804Follow only command line symbolic links while performing a physical file 805system traversal. 806.It Fl L 807Follow all symbolic links to perform a logical file system traversal. 808.It Fl T Ar [from_date][,to_date][/[c][m]] 809Allow files to be selected based on a file modification or inode change 810time falling within a specified time range of 811.Ar from_date 812to 813.Ar to_date 814(the dates are inclusive). 815If only a 816.Ar from_date 817is supplied, all files with a modification or inode change time 818equal to or younger are selected. 819If only a 820.Ar to_date 821is supplied, all files with a modification or inode change time 822equal to or older will be selected. 823When the 824.Ar from_date 825is equal to the 826.Ar to_date , 827only files with a modification or inode change time of exactly that 828time will be selected. 829.Pp 830When 831.Nm pax 832is in the 833.Em write 834or 835.Em copy 836mode, the optional trailing field 837.Ar [c][m] 838can be used to determine which file time (inode change, file modification or 839both) are used in the comparison. 840If neither is specified, the default is to use file modification time only. 841The 842.Ar m 843specifies the comparison of file modification time (the time when 844the file was last written). 845The 846.Ar c 847specifies the comparison of inode change time (the time when the file 848inode was last changed; e.g. a change of owner, group, mode, etc). 849When 850.Ar c 851and 852.Ar m 853are both specified, then the modification and inode change times are 854both compared. 855The inode change time comparison is useful in selecting files whose 856attributes were recently changed or selecting files which were recently 857created and had their modification time reset to an older time (as what 858happens when a file is extracted from an archive and the modification time 859is preserved). 860Time comparisons using both file times is useful when 861.Nm pax 862is used to create a time based incremental archive (only files that were 863changed during a specified time range will be archived). 864.Pp 865A time range is made up of six different fields and each field must contain two 866digits. 867The format is: 868.Dl [yy[mm[dd[hh]]]]mm[.ss] 869Where 870.Cm yy 871is the last two digits of the year, 872the first 873.Cm mm 874is the month (from 01 to 12), 875.Cm dd 876is the day of the month (from 01 to 31), 877.Cm hh 878is the hour of the day (from 00 to 23), 879the second 880.Cm mm 881is the minute (from 00 to 59), 882and 883.Cm ss 884is the seconds (from 00 to 59). 885The minute field 886.Cm mm 887is required, while the other fields are optional and must be added in the 888following order: 889.Dl Cm hh , dd , mm , yy . 890The 891.Cm ss 892field may be added independently of the other fields. 893Time ranges are relative to the current time, so 894.Dl Fl T Ar 1234/cm 895would select all files with a modification or inode change time 896of 12:34 PM today or later. 897Multiple 898.Fl T 899time range can be supplied and checking stops with the first match. 900.It Fl U Ar user 901Select a file based on its 902.Ar user 903name, or when starting with a 904.Cm # , 905a numeric uid. 906A '\\' can be used to escape the 907.Cm # . 908Multiple 909.Fl U 910options may be supplied and checking stops with the first match. 911.It Fl X 912When traversing the file hierarchy specified by a pathname, 913do not descend into directories that have a different device ID. 914See the 915.Li st_dev 916field as described in 917.Xr stat 2 918for more information about device ID's. 919.It Fl Y 920This option is the same as the 921.Fl D 922option, except that the inode change time is checked using the 923pathname created after all the file name modifications have completed. 924.It Fl Z 925This option is the same as the 926.Fl u 927option, except that the modification time is checked using the 928pathname created after all the file name modifications have completed. 929.El 930.Pp 931The options that operate on the names of files or archive members ( 932.Fl c , 933.Fl i , 934.Fl n , 935.Fl s , 936.Fl u , 937.Fl v , 938.Fl D , 939.Fl G , 940.Fl T , 941.Fl U , 942.Fl Y , 943and 944.Fl Z ) 945interact as follows. 946.Pp 947When extracting files during a 948.Em read 949operation, archive members are 950.Sq selected , 951based only on the user specified pattern operands as modified by the 952.Fl c , 953.Fl n , 954.Fl u , 955.Fl D , 956.Fl G , 957.Fl T , 958.Fl U 959options. 960Then any 961.Fl s 962and 963.Fl i 964options will modify in that order, the names of these selected files. 965Then the 966.Fl Y 967and 968.Fl Z 969options will be applied based on the final pathname. 970Finally the 971.Fl v 972option will write the names resulting from these modifications. 973.Pp 974When archiving files during a 975.Em write 976operation, or copying files during a 977.Em copy 978operation, archive members are 979.Sq selected , 980based only on the user specified pathnames as modified by the 981.Fl n , 982.Fl u , 983.Fl D , 984.Fl G , 985.Fl T , 986and 987.Fl U 988options (the 989.Fl D 990option only applies during a copy operation). 991Then any 992.Fl s 993and 994.Fl i 995options will modify in that order, the names of these selected files. 996Then during a 997.Em copy 998operation the 999.Fl Y 1000and the 1001.Fl Z 1002options will be applied based on the final pathname. 1003Finally the 1004.Fl v 1005option will write the names resulting from these modifications. 1006.Pp 1007When one or both of the 1008.Fl u 1009or 1010.Fl D 1011options are specified along with the 1012.Fl n 1013option, a file is not considered selected unless it is newer 1014than the file to which it is compared. 1015.Sh EXAMPLES 1016The command: 1017.Dl pax -w -f /dev/rst0 .\ 1018copies the contents of the current directory to the device 1019.Pa /dev/rst0 . 1020.Pp 1021The command: 1022.Dl pax -r -v -f filename 1023gives the verbose table of contents for an archive stored in 1024.Pa filename . 1025.Pp 1026The following commands: 1027.Dl mkdir newdir 1028.Dl cd olddir 1029.Dl pax -rw .\ newdir 1030will copy the entire 1031.Pa olddir 1032directory hierarchy to 1033.Pa newdir . 1034.Pp 1035The command: 1036.Dl pax -r -s ',^//*usr//*,,' -f a.pax 1037reads the archive 1038.Pa a.pax , 1039with all files rooted in ``/usr'' into the archive extracted relative to the 1040current directory. 1041.Pp 1042The command: 1043.Dl pax -rw -i .\ dest_dir 1044can be used to interactively select the files to copy from the current 1045directory to 1046.Pa dest_dir . 1047.Pp 1048The command: 1049.Dl pax -r -pe -U root -G bin -f a.pax 1050will extract all files from the archive 1051.Pa a.pax 1052which are owned by 1053.Em root 1054with group 1055.Em bin 1056and will preserve all file permissions. 1057.Pp 1058The command: 1059.Dl pax -r -w -v -Y -Z home /backup 1060will update (and list) only those files in the destination directory 1061.Pa /backup 1062which are older (less recent inode change or file modification times) than 1063files with the same name found in the source file tree 1064.Pa home . 1065.Sh STANDARDS 1066The 1067.Nm pax 1068utility is a superset of the 1069.St -p1003.2 1070standard. 1071The options 1072.Fl B , 1073.Fl D , 1074.Fl E , 1075.Fl G , 1076.Fl H , 1077.Fl T , 1078.Fl U , 1079.Fl Y , 1080.Fl Z , 1081the archive formats 1082.Ar bcpio , 1083.Ar sv4cpio , 1084.Ar sv4crc , 1085.Ar tar , 1086and the flawed archive handling during 1087.Ar list 1088and 1089.Ar read 1090operations are extensions to the 1091.Tn POSIX 1092standard. 1093.Sh AUTHOR 1094Keith Muller at the University of California, San Diego 1095.Sh ERRORS 1096.Nm pax 1097will exit with one of the following values: 1098.Bl -tag -width 2n 1099.It 0 1100All files were processed successfully. 1101.It 1 1102An error occurred. 1103.El 1104.Pp 1105Whenever 1106.Nm pax 1107cannot create a file or a link when reading an archive or cannot 1108find a file when writing an archive, or cannot preserve the user ID, 1109group ID, or file mode when the 1110.Fl p 1111option is specified, a diagnostic message is written to 1112.Dv standard error 1113and a non-zero exit status will be returned, but processing will continue. 1114In the case where pax cannot create a link to a file, 1115.Nm pax 1116will not create a second copy of the file. 1117.Pp 1118If the extraction of a file from an archive is prematurely terminated by 1119a signal or error, 1120.Nm pax 1121may have only partially extracted a file the user wanted. 1122Additionally, the file modes of extracted files and directories 1123may have incorrect file bits, and the modification and access times may be 1124wrong. 1125.Pp 1126If the creation of an archive is prematurely terminated by a signal or error, 1127.Nm pax 1128may have only partially created the archive which may violate the specific 1129archive format specification. 1130.Pp 1131If while doing a 1132.Em copy , 1133.Nm pax 1134detects a file is about to overwrite itself, the file is not copied, 1135a diagnostic message is written to 1136.Dv standard error 1137and when 1138.Nm pax 1139completes it will exit with a non-zero exit status. 1140