1 GNU tar NEWS - User visible changes. 2011-03-12
2 Please send GNU tar bug reports to <bug-tar@gnu.org>
5 version 1.26 - Sergey Poznyakoff, 2011-03-12
9 ** Fix the --verify option, which broke in version 1.24.
11 ** Fix storing long sparse file names in PAX archives.
13 ** Fix correctness of --atime-preserve=replace
15 tar --atime-preserve=replace no longer tries to restore atime of
18 ** Work around POSIX incompatibilities on FreeBSD, NetBSD and Tru64
20 ** Fix bug with --one-file-system --listed-incremental
22 When invoked with these two options, tar 1.25 would add only the
23 top-level directory to the archive, but not its contents.
26 version 1.25 - Sergey Poznyakoff, 2010-11-07
28 * Fix extraction of empty directories with the -C option in effect.
29 * Fix extraction of device nodes.
30 * Make sure name matching occurs before eventual name transformation.
32 Tar 1.24 changed the ordering of name matching and name transformation
33 so that the former saw already transformed file names. This made it
34 impossible to match file names in certain cases. It is fixed now.
36 * Fix the behavior of tar -x --overwrite on hosts lacking O_NOFOLLOW.
38 * Improve the testsuite.
40 * Alternative decompression programs.
42 If extraction from a compressed archive fails because the corresponding
43 compression program is not installed and the following two conditions
44 are met, tar retries extraction using an alternative decompressor:
46 1. Another compression program supported by tar is able to handle this
48 2. The compression program was not explicitly requested in the command
49 line by the use of such options as -z, -j, etc.
51 For example, if `compress' is not available, tar will try `gzip'.
54 version 1.24 - Sergey Poznyakoff, 2010-10-24
56 * The --full-time option.
58 New command line option `--full-time' instructs tar to output file
59 time stamps to the full resolution.
63 ** More reliable directory traversal when creating archives
65 Tar now checks for inconsistencies caused when a file system is
66 modified while tar is creating an archive. In the new approach, tar
67 maintains a cache of file descriptors to directories, so it uses more
68 file descriptors than before, but it adjusts to system limits on
69 the number of file descriptors. Tar also takes more care when
70 a file system is modified while tar is extracting from an archive.
72 The new checks are implemented via the openat and related calls
73 standardized by POSIX.1-2008. On an older system where these calls do
74 not exist or do not return useful results, tar emulates the calls at
75 some cost in efficiency and reliability.
77 ** Symbolic link attributes
79 When extracting symbolic links, tar now restores attributes such as
80 last-modified time and link permissions, if the operating system
81 supports this. For example, recent versions of the Linux kernel
82 support setting times on symlinks, and some BSD kernels also support
85 ** --dereference consistency
87 The --dereference (-h) option now applies to files that are copied
88 into or out of archives, independently of other options. For example,
89 if F is a symbolic link and archive.tar contains a regular-file member
90 also named F, "tar --overwrite -x -f archive.tar F" now overwrites F
91 itself, rather than the file that F points to. (To overwrite the file
92 that F points to, add the --dereference (-h) option.) Formerly,
93 --dereference was intended to apply only when using the -c option, but
94 the implementation was not consistent.
96 Also, the --dereference option no longer affects accesses to other
97 files, such as archives and time stamp files. Symbolic links to these
98 files are always followed. Previously, the links were usually but not
101 ** Spurious error diagnostics on broken pipe.
103 When receiving SIGPIPE, tar would exit with error status and
104 "write error" diagnostics. In particular, this occurred if
105 invoked as in the example below:
107 tar tf archive.tar | head -n 1
111 `Tar --remove-files' failed to remove a directory which contained
112 symlinks to another files within that directory.
114 ** --test-label behavior
116 In case of a mismatch, `tar --test-label LABEL' exits with code 1,
117 not 2 as it did in previous versions.
119 The `--verbose' option used with `--test-label' provides additional
122 Several volume labels may be specified in a command line, e.g.:
124 tar --test-label -f archive 'My volume' 'New volume' 'Test volume'
126 In this case, tar exits with code 0 if any one of the arguments
127 matches the actual volume label.
129 ** --label used with --update
131 The `--label' option can be used with `--update' to prevent accidental
132 update of an archive:
134 tar -rf archive --label 'My volume' .
136 This did not work in previous versions, in spite of what the docs said.
138 ** --record-size and --tape-length (-L) options
140 Usual size suffixes are allowed for these options. For example,
141 -L10k stands for a 10 kilobyte tape length.
143 ** Fix dead loop on extracting existing symlinks with the -k option.
146 version 1.23 - Sergey Poznyakoff, 2010-03-10
148 * Record size autodetection
150 When listing or extracting archives, the actual record size is
151 reported only if the archive is read from a device (as opposed
152 to regular files and pipes).
156 When a read-only operation (e.g. --list or --extract) is requested
157 on a regular file, tar attemtps to speed up accesses by using lseek.
159 * New command line option `--warning'
161 The `--warning' command line option allows to suppress or enable
162 particular warning messages during `tar' run. It takes a single
163 argument (a `keyword'), identifying the class of warning messages
164 to affect. If the argument is prefixed with `no-', such warning
165 messages are suppressed. For example,
167 tar --warning=no-alone-zero-block -x -f archive
169 suppresses the output of `A lone zero block' diagnostics, which is
170 normally issued if `archive' ends with a single block of zeros.
172 See Tar Manual, section 3.9 "Controlling Warning Messages", for a
175 * New command line option `--level'
177 The `--level=N' option sets the incremental dump level N. It
178 is valid when used in conjunction with the -c and --listed-incremental
179 options. So far the only meaningful value for N is 0. The
180 `--level=0' option forces creating the level 0 dump, by truncating
181 the snapshot file if it exists.
183 * Files removed during incremental dumps
185 If a file or directory is removed while incremental dump is
186 in progress, tar exact actions depend on whether this file
187 was explicitly listed in the command line, or was found
188 during file system scan.
190 If the file was explicitly listed in the command line, tar
191 issues error message and exits with the code 2, meaning
194 Otherwise, if the file was found during the file system scan,
195 tar issues a warning, saying "File removed before we read it",
196 and sets exit code to 1, which means "some files differ".
197 If the --warning=no-file-removed option is given, no warning
198 is issued and exit code remains 0.
200 * Modification times of PAX extended headers.
202 Modification times in ustar header blocks of extended headers
203 are set to mtimes of the corresponding archive members. This
204 can be overridden by the
206 --pax-opion='exthdr.mtime=STRING'
208 command line option. The STRING is either number of seconds since
209 the Epoch or a `Time reference' (see below).
211 Modification times in ustar header blocks of global extended
212 headers are set to the time when tar was invoked.
214 This can be overridden by the
216 --pax-opion='globexthdr.mtime=STRING'
218 command line option. The STRING is either number of seconds since
219 the Epoch or a `Time reference' (see below).
221 * Time references in --pax-option argument.
223 Any value from the --pax-option argument that is enclosed in a pair
224 of curly braces represents a time reference. The string between the
225 braces is understood either as a textual time representation, as described in
226 chapter 7, "Date input formats", of the Tar manual, or as a name of
227 an existing file, starting with `/' or `.'. In the latter
228 case, it is replaced with the modification time of that file.
230 * Environment of --to-command script.
232 The environment passed to the --to-command script is extended with
233 the following variables:
235 TAR_VERSION GNU tar version number
236 TAR_ARCHIVE The name of the archive
237 TAR_VOLUME Ordinal number of the volume
238 TAR_FORMAT Format of the archive
239 TAR_BLOCKING_FACTOR Current blocking factor
242 ** Fix handling of hard link targets by -c --transform.
243 ** Fix hard links recognition with -c --remove-files.
244 ** Fix restoring files from backup (debian bug #508199).
245 ** Correctly restore modes and permissions on existing directories.
246 ** The --remove-files option removes files only if they were
247 succesfully stored in the archive.
248 ** Fix storing and listing of the volume labels in POSIX format.
249 ** Improve algorithm for splitting long file names (ustar
251 ** Fix possible memory overflow in the rmt client code (CVE-2010-0624).
254 version 1.22 - Sergey Poznyakoff, 2009-03-05
256 * Support for xz compression
258 Tar uses xz for compression if one of the following conditions is met:
260 1. The option --xz or -J (see below) is used.
261 2. The xz binary is set as compressor using --use-compress-program option.
262 3. The file name of the archive being created ends in `.xz' and
263 auto-compress option (-a) is used.
265 Xz is used for decompression if one of the following conditions is met:
267 1. The option --xz or -J is used.
268 2. The xz binary is set as compressor using --use-compress-program option.
269 3. The file is recognized as xz compressed stream data.
271 * Short option -J reassigned as a short equivalent of --xz
275 The -I option is assigned as a short equivalent for
276 --use-compress-program.
278 * The --no-recursive option works in incremental mode.
281 version 1.21 - Sergey Poznyakoff, 2008-12-27
283 * New short option -J
285 A shortcut for --lzma.
289 * New option --no-auto-compress
291 Cancels the effect of previous --auto-compress (-a) option.
293 * New option --no-null
295 Cancels the effect of previous --null option.
297 * Compressed format recognition
299 If tar is unable to determine archive compression format, it falls
300 back to using archive suffix to determine it.
304 Using --exclude-vcs handles also files used internally by Bazaar,
307 * Transformation scope flags
309 Name transformation expressions understand additional flags that
310 control type of archive members affected by them. The flags are:
313 Apply transformation to regular archive members.
316 Apply transformation to symbolic link targets.
319 Apply transformation to hard link targets.
321 Corresponding upper-case letters negate the meaning, so that
322 `H' means ``do not apply transformation to hard link targets.''
324 The scope flags are listed in the third part of an `s' expression,
327 tar --transform 's|^|/usr/local/|S'
329 Default is `rsh', which means that transformations are applied to
330 both regular archive members and to the targets of symbolic and hard
331 links. If several transform expressions are used, the default flags
332 can be changed using `flags=' statement before the expressions, e.g.:
334 tar --transform 'flags=S;s|^|/usr/local/|S'
338 ** The --null option disabled handling of tar options in list files. This
340 ** Fixed record size autodetection. If the detected record size differs from
341 the expected value (either default one, or the one set from the
342 command line), tar always prints a warning if verbosity level is set
343 to 1 or greater, i.e. if either -t or -v option is given.
347 version 1.20 - Sergey Poznyakoff, 2008-04-14
349 * New option --auto-compress (-a)
351 With --create, selects compression algorithm basing on the suffix
352 of the archive file name.
356 Selects LZMA compression algorithm
358 * New option --hard-dereference
360 During archive creation, dereferences hard links and stores the files
361 they refer to, instead of creating usual hard link members (type '1').
363 * New option --checkpoint-action
365 This action allows to specify an action to be executed upon hitting a
366 checkpoint. Recognized actions are: dot, echo (the default),
367 echo=string, ttyout=string, exec=cmdline, and sleep=value. Any number
368 of `--checkpoint-action' options can be specified, the actions will be
369 executed in order of their appearance in the command line. See
370 chapter 3.8 "Checkpoints" for a complete description.
372 * New options --no-check-device, --check-device.
374 The `--no-check-device' option disables comparing device numbers during
375 preparatory stage of an incremental dump. This allows to avoid
376 creating full dumps if the device numbers change (e.g. when using an
379 The `--check-device' option enables comparing device numbers. This is
380 the default. This option is provided to undo the effect of the previous
381 `--no-check-device' option, e.g. if it was set in TAR_OPTIONS
382 environment variable.
384 * The --transform option.
386 Any number of `--transform' options can be given in the command line.
387 The specified transformations will be applied in turn.
389 The argument to `--transform' option can be a list of replace
390 expressions, separated by a semicolon (as in `sed').
392 Filename transformations are applied to symbolic link targets
393 during both creation and extraction. Tar 1.19 used them only
396 For a detailed description, see chapter 6.7 "Modifying File and Member
399 * Info (end-of-volume) scripts
401 The value of the blocking factor is made available to info and
402 checkpoint scripts via environment variable TAR_BLOCKING_FACTOR.
404 * Incremental archives
406 Improved (sped up) extracting from incremental archives.
409 ** Fix bug introduced in version 1.19: tar refused to update non-existing
413 version 1.19 - Sergey Poznyakoff, 2007-10-10
415 * New option --exclude-vcs
417 Excludes directories and files, created by several widely used version
418 control systems, e.g. "CVS/", ".svn/", etc.
420 * --exclude-tag and --exclude-cache options
422 The following options now work with incremental archives as well:
430 * Fix handling of renamed files in listed incremental archives.
432 Previous versions always stored absolute file names in rename
433 records, even if -P was not used. This is fixed: rename records
434 contain file names processed in accordance with the command line
437 * Fix --version output.
439 * Recognition of broken archives.
441 When supplied an archive smaller than 512 bytes in reading mode (-x,
442 -t), the previous version of tar silently ignored it, exiting with
443 code 0. It is fixed. Tar now issues the following diagnostic message:
444 'This does not look like a tar archive', and exits with code 2.
446 * Fix double-dot recognition in archive member names in case of duplicate '/.'.
448 * Fix file padding in case of truncation of the input file to zero size.
451 version 1.18 - Sergey Poznyakoff, 2007-06-29
453 * Licensed under the GPLv3
455 * Fixed several bugs in the testsuite
458 version 1.17 - Sergey Poznyakoff, 2007-06-08
460 * Fix archivation of sparse files in posix mode. Previous versions padded
461 sparse members with spurious zero blocks.
463 * Fix operation of --verify --listed-incremental. Version 1.16.1 produced
464 a full dump when both options were given.
466 * Fix --occurrence. In previous versions it continued scanning the archive
467 even though all requested members has already been extracted.
469 * Scope of --transform and --strip-components options.
471 In addition to affecting regular archive members, the --transform
472 option affects hard and soft link targets and the --strip-components
473 option affects hard link targets as well.
475 * End-of-volume script can send the new volume name to tar by writing
476 it to the file descriptor stored in the environment variable `TAR_FD'.
479 version 1.16.1 - Sergey Poznyakoff, 2006-12-09
481 * New option --exclude-tag allows to specify "exclusion tag files", i.e.
482 files whose presence in a directory means that the directory should not
485 * The --exclude-cache option excludes directories that contain the
486 CACHEDIR.TAG file from being archived. Previous versions excluded
487 directory contents only, while the directories themselves were
488 still added to the archive.
490 * Support for reading ustar type 'N' header logical records has been removed.
491 This GNU extension was generated only by very old versions of GNU 'tar'.
492 Unfortunately its implementation had security holes; see
493 <http://archives.neohapsis.com/archives/fulldisclosure/2006-11/0344.html>.
494 We don't expect that any tar archives in practical use have type 'N'
495 records, but if you have one and you trust its contents, you can
496 decode it with GNU tar 1.16 or earlier.
498 * Race conditions have been fixed that in some cases briefly allowed
499 files extracted by 'tar -x --same-owner' (or plain 'tar -x', when
500 running as root) to be accessed by users that they shouldn't have been.
503 version 1.16 - Sergey Poznyakoff, 2006-10-21
505 * After creating an archive, tar exits with code 1 if some files were
506 changed while being read. Previous versions exited with code 2 (fatal
507 error), and only if some files were truncated while being archived.
509 * New option --mtime allows to set modification times for all archive
510 members during creation.
513 ** Avoid running off file descriptors when using multiple -C options.
514 ** tar --index-file=FILE --file=- sent the archive to FILE, and
515 the listing to stderr.
518 version 1.15.91 - Sergey Poznyakoff, 2006-06-16
520 * Incompatible changes
524 Previous versions of GNU tar assumed shell-style globbing when
525 extracting from or listing an archive. For example:
529 would extract all files whose names end in '.c'. This behavior
530 was not documented and was incompatible with traditional tar
531 implementations. Therefore, starting from this version, GNU tar
532 no longer uses globbing by default. For example, the above invocation
533 is now interpreted as a request to extract from the archive the file
536 To treat member names as globbing patterns, use --wildcards option.
537 If you wish tar to mimic the behavior of versions up to 1.15.90,
538 add --wildcards to the value of the environment variable TAR_OPTIONS.
540 The exact way in which tar interprets member names is controlled by the
541 following command line options:
543 --wildcards use wildcards
544 --anchored patterns match file name start
545 --ignore-case ignore case
546 --wildcards-match-slash wildcards match `/'
548 Each of these options has a '--no-' counterpart that disables its
549 effect (e.g. --no-wildcards).
551 These options affect both the interpretation of member names from
552 command line and that of the exclusion patterns (given with --exclude
553 and --exclude-from options). The defaults are:
555 1. For member names: --no-wildcards --anchored
556 2. For exclusion patterns: --wildcards --no-anchored --wildcards-match-slash
558 The options can appear multiple times in the command line, thereby
559 changing the way command line arguments are interpreted. For example,
560 to use case-insensitive matching in exclude patterns and to revert to
561 case-sensitive matching for the rest of command line, one could write:
563 tar xf foo.tar --ignore-case --exclude-from=FILE --no-ignore-case file.name
565 ** Short option -l is now an alias of --check-links option, which complies
566 with UNIX98. This ends the transition period started with version 1.14.
570 ** New option --transform allows to transform file names before storing them
571 in the archive or member names before extracting. The option takes a
572 sed replace expression as its argument. For example,
574 tar cf foo.tar --transform 's,^,prefix/,'
576 will add 'prefix/' to all file names stored in foo.tar.
578 ** --strip-components option works when deleting and comparing. In previous
579 versions it worked only with --extract.
581 ** New option --show-transformed-names enables display of transformed file
582 or archive. It generalizes --show-stored-names option, introduced in
583 1.15.90. In particular, when creating an archive in verbose mode, it lists
584 member names as stored in the archive, i.e., with any eventual prefixes
585 removed and file name transformations applied. The option is useful,
586 for example, while comparing `tar cv' and `tar tv' outputs.
588 ** New incremental snapshot file format keeps information about file names
589 as well as that about directories.
591 ** The --checkpoint option takes an optional argument specifying the number
592 of records between the two successive checkpoints. Optional dot
593 starting the argument intructs tar to print dots instead of textual
596 ** The --totals option can be used with any tar operation (previous versions
597 understood it only with --create). If an argument to this option is
598 given, it specifies the signal upon delivery of which the statistics
599 is to be printed. Both forms of this option (with and without
600 argument) can be given to in a single invocation of tar.
603 ** Detect attempts to update compressed archives.
606 version 1.15.90 - Sergey Poznyakoff, 2006-02-19
610 ** Any number of -T (--files-from) options may be used in the command line.
611 The file specified with -T may include any valid `tar' options,
612 including another -T option.
613 Compatibility note: older versions of tar would only recognize -C
614 as an option name within the file list file. Now any file whose name
615 starts with - is handled as an option. To insert file names starting with
616 dash, use the --add-file option.
618 ** List files containing null-separated file names are detected and processed
619 automatically. It is no longer necessary to give the --null option.
621 ** New option --no-unquote disables the unquoting of input file names.
622 This is useful for processing output from `find dir -print0'.
623 An orthogonal option --unquote is provided as well.
625 ** New option --test-label tests the archive volume label.
626 If an argument is specified, the label is compared against its value.
627 Tar exits with code 0 if the two strings match, and with code 2 if
630 If no argument is given, the --verbose option is implied. In this case,
631 tar prints the label name if present and exits with code 0.
633 ** New option --show-stored-names. When creating an archive in verbose mode,
634 it lists member names as stored in the archive, i.e., with any eventual
635 prefixes removed. The option is useful, for example, while comparing
636 `tar cv' and `tar tv' outputs.
638 ** New option --to-command pipes the contents of archive members to the
641 ** New option --atime-preserve=system, which uses the O_NOATIME feature
642 of recent Linux kernels to avoid some problems when preserving file
645 ** New option --delay-directory-restore delays restoring modification times
646 and permissions of extracted directories until the end of extraction.
647 This is necessary for restoring from archives with unusual member
648 ordering (in particular, those created with --no-recursion option).
649 This option is implied when restoring from incremental archives.
651 ** New option --restrict prohibits use of some potentially harmful tar
652 options. Currently it disables '!' escape in multi-volume name menu.
654 ** New options --quoting-style and --quote-chars control the way tar
655 quotes member names on output. The --quoting-style takes an argument
656 specifying the quoting style to use (literal, shell, shell-always,
657 c, escape, locale, clocale). The argument to --quote-chars is a string
658 specifying characters to quote, even if the selected quoting style
659 would not quote them otherwise. The option --no-quote-chars is
660 provided to disable quoting certain characters.
662 ** The end-of-volume script (introduced with --info-script option) can
663 get current archive name from the environment variable TAR_ARCHIVE and
664 the volume number from the variable TAR_VOLUME. It can alter the
665 archive name by writing new name to the file descriptor 3.
667 ** Better support for full-resolution time stamps. Tar cannot restore
668 time stamps to full nanosecond resolution, though, until the kernel
669 guys get their act together and give us a system call to set file time
670 stamps to nanosecond resolution.
672 ** The -v option now prints time stamps only to 1-minute resolution,
673 not full resolution, to avoid using up too many output columns.
674 Nanosecond resolution is now supported, but that would be too much.
678 ** Allow non-option arguments to be interspersed with options.
679 ** When extracting or listing archives in old GNU format, tar
680 used to read an extra block of data after a long name header
681 if length of the member name was divisible by block size (512).
682 Consequently, the file pointer was set off and the next member
683 was not processed correctly.
684 ** Previous version created invalid archives when files shrink
686 ** Compare mode (tar d) hung when trying to compare file contents.
687 ** Previous versions in certain cases failed to restore directory
689 ** When creating an archive, do not attempt to store files whose
690 meta-data cannot be stored in the header due to format limitations
691 (for ustar and v7 formats).
692 ** The --version option now also outputs information about copyright,
693 license, and credits. This reverts to the behavior of tar 1.14 and
694 earlier, and conforms to the GNU coding standards. The --license (-L)
695 option introduced in tar 1.15 has been removed, since it's no longer
699 version 1.15.1 - Sergey Poznyakoff, 2004-12-21
701 This version fixes a bug introduced in 1.15 which caused
702 tar to refuse to extract files from standard input.
705 version 1.15 - Sergey Poznyakoff, 2004-12-20
707 * Compressed archives are recognised automatically, it is no longer
708 necessary to specify -Z, -z, or -j options to read them. Thus, you can
709 now run `tar tf archive.tar.gz'.
711 * When restoring incremental dumps, --one-file-system option
712 prevents directory hierarchies residing on different devices
715 With the previous versions of tar it was dangerous to create
716 incremental dumps with --one-file-system option, since they
717 would recursively remove mount points when restoring from the
718 back up. This change fixes the bug.
720 * Renamed --strip-path to --strip-components for consistency with
723 * Skipping archive members is sped up if the archive media supports
726 * Restore script starts restoring only if it is given --all (-a) option,
727 or some patterns. This is to prevent accidental restores.
729 * `tar --verify' prints a warning if during archive creation some of
730 the file names had their prefixes stripped off.
732 * New option --exclude-caches instructs tar to exclude cache directories
733 automatically on archive creation. Cache directories are those
734 containing a standardized tag file, as specified at:
736 http://www.brynosaurus.com/cachedir/spec.html
738 * New configure option --with-rmt allows to specify full path name to
739 the `rmt' utility. This supersedes DEFAULT_RMT_COMMAND variable
740 introduced in version 1.14
742 * New configure variable DEFAULT_RMT_DIR allows to specify the directory
743 where to install `rmt' utility. This is necessary since modifying
744 --libexecdir as was suggested for version 1.14 produced a side effect: it
745 also modified installation prefix for backup scripts (if
746 --enable-backup-scripts was given).
749 ** Fixed flow in recognizing files to be included in incremental dumps.
750 ** Correctly recognize sparse archive members when used with -T option.
751 ** GNU multivolume headers cannot store filenames longer than 100 characters.
752 Do not allow multivolume archives to begin with such filenames.
753 ** If a member with link count > 2 was stored in the archive twice,
754 previous versions of tar were not able to extract it, since they
755 were trying to link the file to itself, which always failed and
756 lead to removing the already extracted copy. Preserve the first
757 extracted copy in such cases.
758 ** Restore script was passing improper argument to tar --listed option (which
759 didn't affect the functionality, but was logically incorrect).
760 ** Fixed verification of created archives.
761 ** Fixed unquoting of file names containing backslash escapes (previous
762 versions failed to recognize \a and \v).
763 ** When attempting to delete a non-existing member from the archive, previous
764 versions of tar used to overwrite last archive block with zeroes.
767 version 1.14 - Sergey Poznyakoff, 2004-05-11
769 * Added support for POSIX.1-2001 and ustar archive formats.
770 * New option --format allows to select the output archive format
771 * The default output format can be selected at configuration time
772 by presetting the environment variable DEFAULT_ARCHIVE_FORMAT.
773 Allowed values are GNU, V7, OLDGNU and POSIX.
774 * New option --strip-path allows to cut off a given number of
775 path elements from the name of the file being extracted.
777 * New options --index-file, --no-overwrite-dir. The --overwrite-dir
778 option is now the default; use --no-overwrite-dir if you prefer
779 the previous default behavior.
781 * The semantics of -o option is changed. When extracting, it
782 does the same as --no-same-owner GNU tar option. This is compatible
783 with UNIX98 tar. Otherwise, its effect is the same as that of
784 --old-archive option. This latter is deprecated and will be removed
787 * New option --check-links prints a message if not all links are dumped
788 for a file being archived. This corresponds to the UNIX98 -l option.
789 The current semantics of the -l option is retained for compatibility
790 with previous releases, however such usage is strongly deprecated as
791 the option will change to its UNIX98 semantics in the future releases.
793 * New option --occurrence[=N] can be used in conjunction with one of
794 the subcommands --delete, --diff, --extract or --list when a list of
795 files is given either on the command line or via -T option. This
796 option instructs tar to process only the Nth occurrence of each named
797 file. N defaults to 1, so `tar -x -f archive --occurrence filename'
798 extracts the first occurrence of `filename' from `archive'
799 and terminates without scanning to the end of the archive.
801 * New option --pax-option allows to control the handling of POSIX
802 keywords in `pax' extended headers. It is equivalent to `pax'
805 * --incremental and --listed-incremental options work correctly on
806 individual files, as well as on directories.
808 * New scripts: backup (replaces old level-0 and level-1) and restore.
809 The scripts are compiled and installed if --enable-backup-scripts
810 option is given to configure.
812 * By default tar searches "rmt" utility in "$prefix/libexec/rmt",
813 which is consistent with the location where the version of "rmt"
814 included in the package is installed. Previous versions of tar
815 used "/etc/rmt". To install "rmt" to its traditional location,
816 run configure with option --libexecdir=/etc. Otherwise, if you
817 already have rmt installed and wish to use it, instead of the
818 shipped in version, set the variable DEFAULT_RMT_COMMAND to
819 the full path name of the utility, e.g., ./configure
820 DEFAULT_RMT_COMMAND=/etc/rmt.
822 Notice also that the full path name of the "rmt" utility to
823 use can be set at runtime, by giving option --rmt-command to
826 * Removed obsolete command line options:
827 ** --absolute-paths superseded by --absolute-names
828 ** --block-compress is not needed any longer
829 ** --block-size superseded by --blocking-factor
830 ** --modification-time superseded by --touch
831 ** --read-full-blocks superseded by --read-full-records
832 ** --record-number superseded by --block-number
833 ** --version-control superseded by --backup
835 * New message translations fi (Finnish), gl (Galician), hr (Croatian),
836 hu (Hungarian), ms (Malaysian), nb (Norwegian), ro (Romanian), sk
837 (Slovak), zh_CN (Chinese simplified), zh_TW (Chinese traditional).
838 The code 'no' for Norwegian (Bokmål) has been withdrawn; use 'nb' instead.
843 version 1.13.25 - Paul Eggert, 2001-09-26
848 version 1.13.24 - Paul Eggert, 2001-09-22
850 * New option --overwrite-dir.
851 * Fixes for buffer overrun, porting, and copyright notice problems.
852 * The message translations for Korean are available again.
855 version 1.13.23 - Paul Eggert, 2001-09-13
857 * Bug, porting, and copyright notice fixes.
860 version 1.13.22 - Paul Eggert, 2001-08-29
865 version 1.13.21 - Paul Eggert, 2001-08-28
867 * Porting and copyright notice fixes.
870 version 1.13.20 - Paul Eggert, 2001-08-27
872 * Some bugs were fixed:
874 - hard links to symbolic links
876 * New option --recursion (the default) that is the inverse of --no-recursion.
878 * New options --anchored, --ignore-case, --wildcards,
879 --wildcards-match-slash, and their negations (e.g., --no-anchored).
880 Along with --recursion and --no-recursion, these options control how
881 exclude patterns are interpreted.
883 * The default interpretation of exclude patterns is now --no-anchored
884 --no-ignore-case --recursion --wildcards --wildcards-match-slash.
885 This is a quiet change to the semantics of --exclude. The previous
886 semantics were a failed attempt at backward compatibility but it
887 became clear that the semantics were puzzling and did not satisfy
888 everybody. Rather than continue to try to revive that dead horse we
889 thought it better to substitute cleaner semantics, with options so
890 that you can change the behavior more to your liking.
892 * New message translations for Indonesian and Turkish.
893 The translation for Korean has been withdrawn due to encoding errors.
894 It will be reissued once those are fixed.
897 version 1.13.19 - Paul Eggert, 2001-01-13
899 * The -I option has been withdrawn, as it was buggy and confusing.
900 Eventually it is planned to be reintroduced, with the same meaning as -T.
902 * With an option like -N DATE, if DATE starts with "/" or ".", it is taken
903 to be a file name; the last-modified time of that file is used as the date.
906 version 1.13.18 - Paul Eggert, 2000-10-29
908 * Some security problems have been fixed. `tar -x' now modifies only
909 files under the working directory, unless you also specify an unsafe
910 option like --absolute-names or --overwrite.
912 * The short name of the --bzip option has been changed to -j,
913 and -I is now an alias for -T, for compatibility with Solaris tar.
915 * The manual is now distributed under the GNU Free Documentation License.
917 * The new environment variable TAR_OPTIONS holds default command-line options.
919 * The --no-recursion option now affects extraction too.
921 * The wording in some diagnostics has been changed slightly.
923 * Snapshot files now record whether each file was accessed via NFS.
924 The new file format is upward- and downward-compatible with the old.
926 * New language supported: da.
928 * Compilation by traditional (K&R) C compilers is no longer supported.
929 If you still use such a compiler, please use GCC instead.
931 * This version of tar works best with GNU gzip test version 1.3 or later.
932 Please see <ftp://alpha.gnu.org/gnu/gzip/>.
934 * `tar --delete -f -' now works again.
937 version 1.13.17 - Paul Eggert, 2000-01-07.
939 * `tar --delete -f -' is no longer allowed; it was too buggy.
940 * Diagnostic messages have been made more regular and consistent.
943 version 1.13.16 - Paul Eggert, 1999-12-13.
945 * By default, tar now refuses to overwrite an existing file when
946 extracting files from an archive; instead, it removes the file
947 before extracting it. If the existing file is a symbolic link, the
948 link is removed and not the pointed-to file. There is one
949 exception: existing nonempty directories are not removed, nor are
950 their ownerships or permissions extracted. This fixes some
951 longstanding security problems.
953 The new --overwrite option enables the old default behavior.
955 For regular files, tar implements this change by using the O_EXCL
956 option of `open' to ensure that it creates the file; if this fails, it
957 removes the file and tries again. This is similar to the behavior of
958 the --unlink-first option, but it is faster in the common case of
959 extracting a new directory.
961 * By default, tar now ignores file names containing a component of `..'
962 when extracting, and warns about such file names when creating an archive.
963 To enable the old behavior, use the -P or --absolute-names option.
965 * Tar now handles file names with multibyte encodings (e.g., UTF-8, Shift-JIS)
966 correctly. It relies on the mbrtowc function to handle multibyte characters.
968 * The file generated by -g or --listed-incremental now uses a format
969 that is independent of locale, so that users need not worry about
970 locale when restoring a backup. This is needed for proper support
971 of multibyte characters. Old-format files can still be read, and
972 older versions of GNU tar can read new-format files, unless member
973 names have multibyte chars.
975 * Many diagnostics have been changed slightly, so that file names are
976 now output unambiguously. File names in diagnostics now are either
977 `quoted like this' (in the default C locale) or are followed by
978 colon, newline, or space, depending on context. Unprintable
979 characters are escaped with a C-like backslash conventions.
980 Terminating characters (e.g., close-quote, colon, newline)
981 are also escaped as needed.
983 * tar now ignores socket files when creating an archive.
984 Previously tar archived sockets as fifos, which caused problems.
987 version 1.13.15 - Paul Eggert, 1999-12-03.
989 * If a file's ctime changes when being archived, report an error.
990 Previously tar looked at mtime, which missed some errors.
993 version 1.13.14 - Paul Eggert, 1999-11-07.
995 * New translations ja, pt_BR.
996 * New options --help and --version for rmt.
997 * Ignore Solaris door files when creating an archive.
1000 version 1.13.13 - Paul Eggert, 1999-10-11.
1002 * Invalid headers in tar files now elicit errors, not just warnings.
1003 * `tar --version' output conforms to the latest GNU coding standards.
1004 * If you specify an invalid date, `tar' now substitutes (time_t) -1.
1005 * `configure --with-dmalloc' is no longer available.
1008 version 1.13.12 - Paul Eggert, 1999-09-24.
1010 * `tar' now supports hard links to symbolic links.
1012 * New options --no-same-owner, --no-same-permissions.
1014 * --total now also outputs a human-readable size, and a throughput value.
1016 * `tar' now uses two's-complement base-256 when outputting header
1017 values that are out of the range of the standard unsigned base-8
1018 format. This affects archive members with negative or huge time
1019 stamps or uids, and archive members 8 GB or larger. The new tar
1020 archives cannot be read by traditional tar, or by older versions of
1021 GNU tar. Use the --old-archive option to revert to the old
1022 behavior, which uses unportable representations for negative values,
1023 and which rejects large files.
1025 * On 32-bit hosts, `tar' now assumes that an incoming time stamp T in
1026 the range 2**31 <= T < 2**32 represents the negative time (T -
1027 2**32). This behavior is nonstandard and is not portable to 64-bit
1028 time_t hosts, so `tar' issues a warning.
1030 * `tar' no longer gives up extracting immediately upon discovering
1031 that an archive contains garbage at the end. It attempts to extract
1032 as many files as possible from the good data before the garbage.
1034 * A read error now causes a nonzero exit status, not just a warning.
1036 * Some diagnostics have been reworded for consistency.
1039 version 1.13.11 - Paul Eggert, 1999-08-23.
1041 * The short name of the --bzip option has been changed to -I,
1042 for compatibility with paxutils.
1044 * -T /dev/null now matches nothing; previously, it matched anything
1045 if no explicit operands were given.
1047 * The `--' option now works the same as with other GNU utilities;
1048 it causes later operands to be interpreted as file names, not options,
1049 even if they begin with `-'.
1051 * For the --newer and --after-date options, the table of time zone
1052 abbreviations like `EST' has been updated to match current practice.
1053 Also, local time abbreviations are now recognized, even if they are
1054 not in tar's hardwired table. Remember, though, that you should use
1055 numeric UTC offsets like `-0500' instead of abbreviations like
1056 `EST', as abbreviations are not standardized and are ambiguous.
1059 version 1.13.10 - Paul Eggert, 1999-08-20.
1061 * `tar' now uses signed base-64 when outputting header values that are
1062 out of the range of the standard unsigned base-8 format. [This
1063 change was superseded in 1.13.12, described above.]
1066 version 1.13.9 - Paul Eggert, 1999-08-18.
1068 * `tar' now writes two zero blocks at end-of-archive instead of just one.
1069 POSIX.1 requires this, and some other `tar' implementations check for it.
1071 * `tar' no longer silently accepts a block containing nonzero checksum bytes
1074 * `tar' now reads buggy tar files that have a null byte at the start of a
1075 numeric header field.
1078 version 1.13.8 - Paul Eggert, 1999-08-16.
1080 * For compatibility with traditional `tar', intermediate directories
1081 created automatically by root are no longer given the uid and gid of
1082 the original file or directory.
1085 version 1.13.7 - Paul Eggert, 1999-08-14.
1087 * --listed-incremental and --newer are now incompatible options.
1089 * When creating an archive, leading `./' is no longer stripped,
1090 to match traditional tar's behavior (and simplify the documentation).
1092 * --diff without --absolute-names no longer falls back on absolute names.
1095 version 1.13.6 - Paul Eggert, 1999-08-11.
1097 * An --exclude pattern containing / now excludes a file only if it matches an
1098 initial prefix of the file name; a pattern without / continues to
1099 exclude a file if it matches any file name component.
1101 * The protocol for talking to rmt has been extended slightly.
1102 Open flags are now communicated in symbolic format as well as numeric.
1103 The symbolic format (e.g., "O_WRONLY|O_CREAT|O_TRUNC") is for portability
1104 when rmt is operating on a different operating system from tar.
1105 The numeric format is retained, and rmt uses it if symbolic format is absent,
1106 for backward compatibility with older versions of tar and rmt.
1108 * When writing GNU tar format headers, tar now uses signed base-64
1109 for values that cannot be represented in unsigned octal.
1110 This supports larger files (2**66 - 1 bytes instead of 2**33 - 1 bytes),
1111 larger uids, negative time stamps, etc.
1113 * When extracting files with unknown ownership, tar now looks up the
1114 uid and gid "nobody" on hosts whose headers do not define UID_NOBODY
1115 and GID_NOBODY, and falls back on uid/gid -2 if there is no "nobody".
1117 * tar -t --numeric-owner now prints numeric uids and gids, not symbolic.
1119 * New option -y or --bzip2 for bzip2 compression, by popular request.
1122 version 1.13.5 - Paul Eggert, 1999-07-20.
1124 * Do the delayed updates of file metadata even after a fatal error.
1127 version 1.13.4 - Paul Eggert, 1999-07-20.
1129 * Do not chmod unless we are root or the -p option was given;
1130 this matches historical practice.
1133 version 1.13.3 - Paul Eggert, 1999-07-16.
1135 * A path name is excluded if any of its file name components matches an
1136 excluded pattern, even if the path name was specified on the command line.
1137 Also see 1.13.6 for later changes in this area.
1140 version 1.13.2 - Paul Eggert, 1999-07-14.
1142 * Bug reporting address changed to <bug-tar@gnu.org>.
1145 version 1.13.1 - Paul Eggert, 1999-07-12.
1149 version 1.13 - Paul Eggert, 1999-07-08.
1151 * Support for large files, e.g., files larger than 2 GB on many 32-bit hosts.
1152 Also, support for larger uids, device ids, etc.
1153 * Many bug fixes and porting fixes.
1154 * This release is only for fixes. A more ambitious test release,
1155 with new features, is available as part of the paxutils. Please see:
1156 ftp://alpha.gnu.org/gnu/paxutils/
1157 The fixes in this release are intended to be merged with paxutils
1158 at some point, but they haven't been merged yet.
1159 * An interim GNU tar alpha had new --bzip2 and --ending-file options,
1160 but they have been removed to maintain compatibility with paxutils.
1161 Please try --use=bzip2 instead of --bzip2.
1163 Version 1.12 - François Pinard, 1997-04.
1166 * Use shell globbing patterns for --label, instead of regular expressions.
1167 * Do not quote anymore internally over the quoting done by the shell.
1170 * Offer internationalization capabilities of most recent GNU gettext.
1171 * Messages available in many more languages, thanks to all translators!
1172 * Usage of ISO 8601 dates in listings, instead of local American dates.
1173 * More normalization and cleanup in error messages.
1176 * For helping using tar with find, offer a --no-recursion option.
1177 * Implement --numeric-owner for ignoring symbolic names at create time.
1178 * New --owner, --group --mode options, still preliminary.
1179 * Recognize creating an archive on /dev/null, so Amanda works faster.
1180 * Object to the creation of an empty archive (like in `tar cf FILE').
1181 * Barely start implementing --posix and POSIXLY_CORRECT.
1184 * Make a better job at restoring file and directory attributes.
1185 * Automatically attempt deleting existing files when in the way.
1186 * Option --unlink-first (-U) removes most files prior to extraction.
1187 * Option --recursive-unlink removes non-empty directories when in the way.
1188 * Option --numeric-owner ignores owner/group names, it uses UID/GID instead.
1189 * Use global umask when creating missing intermediate directories.
1190 * When symlinks are not available, extract symbolic links as hard links.
1191 * Diagnose extraction of contiguous files as regular files.
1192 * New --backup, --suffix and --version-control options.
1195 * Better support of huge archives with --tape-length and --totals.
1196 * Rename option --read-full-blocks (-B) to --read-full-records (-B).
1197 * Rename option --block-size (-b) to --blocking-factor (-b).
1198 * Rename option --record-number (-R) to --block-number (-R).
1199 * With --block-number (-R), report null blocks and end of file.
1200 * Implement --record-size for introducing a size in bytes.
1201 * Delete --block-compress option and rather decide it automatically.
1202 * Rename option --modification-time to --touch.
1204 Many bugs are squashed, while others still run free.
1206 Version 1.11.8 - François Pinard, 1995-06.
1208 * Messages available in French, German, Portuguese and Swedish.
1209 * The distribution provides a rudimentary Texinfo manual.
1210 * The device defaults to stdin/stdout, unless overridden by the installer.
1211 * Option --sparse (-S) should work on more systems.
1212 * Option --rsh-command may select an alternative remote shell program.
1214 Most changes are internal, and should yield better portability.
1216 Version 1.11.2 - Michael Bushnell, 1993-03.
1218 * Changes in backup scripts: cleaned up considerably; notices error
1219 conditions better over rsh; DUMP_REMIND_SCRIPT is now an option in
1220 backup-specs; new file dump-remind is an example of a
1223 * Superfluous "Reading dirname" was a bug; fixed.
1225 * Incompatibility problems with a bug on Solaris are fixed.
1227 * New option --gzip (aliases are --ungzip and -z); calls gzip instead
1228 of compress. Also, --use-compress-program lets you specify any
1229 compress program. --compress-block is renamed --block-compress and
1230 now requires one of the three compression options to be specified.
1232 * Several error messages are cleaned up.
1234 * Directory owners are now set properly when running as root.
1236 * Provide DUMP_REMIND_SCRIPT in backup-specs as a possible option
1239 * Behave better with broken rmt servers.
1241 * Dump scripts no longer use --atime-preserve; this causes a nasty probem.
1243 * Several Makefile cleanups.
1245 Version 1.11.1 - Michael Bushnell, 1992-09.
1249 Version 1.11 - Michael Bushnell, 1992-09.
1250 Version 1.10.16 - 1992-07.
1251 Version 1.10.15 - 1992-06.
1252 Version 1.10.14 - 1992-05.
1253 Version 1.10.13 - 1992-01.
1257 * Now uses GNU standard configure, generated by Autoconf.
1259 * Long options now use `--'; use of `+' is deprecated and support
1260 for it will eventually be removed.
1262 * New option --null causes filenames read by -T to be
1263 null-terminated, and causes -C to be ignored.
1265 * New option --remove-files deletes files (but not directories)
1266 after they are added to the archive.
1268 * New option --ignore-failed-read prevents read-errors from affecting
1271 * New option --checkpoint prints occasional messages as the tape
1272 is being read or written.
1274 * New option --show-omitted-dirs prints the names of directories
1275 omitted from the archive.
1277 * Some tape drives which use a non-standard method of indicating
1278 end-of-tape now work correctly with multi-tape archives.
1280 * --volno-file: Read the volume number used in prompting the user
1281 (but not in recording volume ID's on the archive) from a file.
1283 * When using --multi-volume, you can now give multiple -f arguments;
1284 the various tape drives will get used in sequence and then wrap
1285 around to the beginning.
1287 * Remote archive names no longer have to be in /dev: any file with a
1288 `:' is interpreted as remote. If new option --force-local is given,
1289 then even archive files with a `:' are considered local.
1291 * New option --atime-preserve restores (if possible) atimes to
1292 their original values after dumping the file.
1294 * No longer does tar confusingly dump "." when you don't tell it
1297 * When extracting directories, tar now correctly restores their
1298 modification and access times.
1300 * Longnames support is redone differently--long name info directly
1301 precedes the long-named file or link in the archive, so you no
1302 longer have to wait for the extract to hit the end of the tape for
1305 Version 1.10 - Michael Bushnell, 1991-07.
1307 * Filename to -G is optional. -C works right. Names +newer and
1308 +newer-mtime work right.
1310 * -g is now +incremental, -G is now +listed-incremental.
1312 * Sparse files now work correctly.
1314 * +volume is now called +label.
1316 * +exclude now takes a filename argument, and +exclude-from does
1317 what +exclude used to do.
1319 * Exit status is now correct.
1321 * +totals keeps track of total I/O and prints it when tar exits.
1323 * When using +label with +extract, the label is now a regexp.
1325 * New option +tape-length (-L) does multi-volume handling like BSD
1326 dump: you tell tar how big the tape is and it will prompt at that
1327 point instead of waiting for a write error.
1329 * New backup scripts level-0 and level-1 which might be useful
1330 to people. They use a file "backup-specs" for information, and
1331 shouldn't need local modification. These are what we use to do
1332 all our backups at the FSF.
1334 Version 1.09 - Jay Fenlason, 1990-10.
1335 Version 1.08 - Jay Fenlason, 1990-01.
1336 Versions 1.07 back to 1.00 by Jay Fenlason.
1338 * See ChangeLog for more details.
1342 Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2003,
1343 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
1345 This file is part of GNU tar.
1347 GNU tar is free software; you can redistribute it and/or modify
1348 it under the terms of the GNU General Public License as published by
1349 the Free Software Foundation; either version 3, or (at your option)
1352 GNU tar is distributed in the hope that it will be useful,
1353 but WITHOUT ANY WARRANTY; without even the implied warranty of
1354 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1355 GNU General Public License for more details.
1357 You should have received a copy of the GNU General Public License
1358 along with tar; see the file COPYING. If not, write to
1359 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
1360 Boston, MA 02110-1301, USA.
1364 paragraph-separate: "[
\f]*$"
1365 eval: (add-hook 'write-file-hooks 'time-stamp)
1366 time-stamp-start: "changes. "
1367 time-stamp-format: "%:y-%02m-%02d"
1368 time-stamp-end: "\n"