1 GNU tar NEWS - User visible changes. 2012-01-18
2 Please send GNU tar bug reports to <bug-tar@gnu.org>
9 In the default C locale, diagnostics and output of 'tar' have been
10 adjusted to quote 'like this' (with apostrophes) instead of `like this'
11 (with an accent grave character and an apostrophe). This tracks
12 recent changes to the GNU coding standards.
16 ** --owner and --group names and numbers
18 The --owner and --group options now accept operands of the form
19 NAME:NUM, so that you can specify both symbolic name and numeric ID
20 for owner and group. In these options, NAME no longer needs to be
21 present in the current host's user and group databases.
23 * The --keep-old-files and --skip-old-files options.
25 This release restores the traditional functionality of the
26 --keep-old-files. This option causes tar to avoid replacing
27 existing files while extracting and to treat such files as errors.
28 Tar will emit a prominent error message upon encountering such files
29 and will exit with code 2 when finished extracting the archive.
31 A new option --skip-old-files is introduced, which acts exactly as
32 --keep-old-files, except that it does not treat existing files as
33 errors. Instead it just silently skips them. An additional level of
34 verbosity can be obtained by using the option --warning=existing-file
35 together with this option.
38 version 1.26 - Sergey Poznyakoff, 2011-03-12
42 ** Fix the --verify option, which broke in version 1.24.
44 ** Fix storing long sparse file names in PAX archives.
46 ** Fix correctness of --atime-preserve=replace
48 tar --atime-preserve=replace no longer tries to restore atime of
51 ** Work around POSIX incompatibilities on FreeBSD, NetBSD and Tru64
53 ** Fix bug with --one-file-system --listed-incremental
55 When invoked with these two options, tar 1.25 would add only the
56 top-level directory to the archive, but not its contents.
59 version 1.25 - Sergey Poznyakoff, 2010-11-07
61 * Fix extraction of empty directories with the -C option in effect.
62 * Fix extraction of device nodes.
63 * Make sure name matching occurs before eventual name transformation.
65 Tar 1.24 changed the ordering of name matching and name transformation
66 so that the former saw already transformed file names. This made it
67 impossible to match file names in certain cases. It is fixed now.
69 * Fix the behavior of tar -x --overwrite on hosts lacking O_NOFOLLOW.
71 * Improve the testsuite.
73 * Alternative decompression programs.
75 If extraction from a compressed archive fails because the corresponding
76 compression program is not installed and the following two conditions
77 are met, tar retries extraction using an alternative decompressor:
79 1. Another compression program supported by tar is able to handle this
81 2. The compression program was not explicitly requested in the command
82 line by the use of such options as -z, -j, etc.
84 For example, if 'compress' is not available, tar will try 'gzip'.
87 version 1.24 - Sergey Poznyakoff, 2010-10-24
89 * The --full-time option.
91 New command line option '--full-time' instructs tar to output file
92 time stamps to the full resolution.
96 ** More reliable directory traversal when creating archives
98 Tar now checks for inconsistencies caused when a file system is
99 modified while tar is creating an archive. In the new approach, tar
100 maintains a cache of file descriptors to directories, so it uses more
101 file descriptors than before, but it adjusts to system limits on
102 the number of file descriptors. Tar also takes more care when
103 a file system is modified while tar is extracting from an archive.
105 The new checks are implemented via the openat and related calls
106 standardized by POSIX.1-2008. On an older system where these calls do
107 not exist or do not return useful results, tar emulates the calls at
108 some cost in efficiency and reliability.
110 ** Symbolic link attributes
112 When extracting symbolic links, tar now restores attributes such as
113 last-modified time and link permissions, if the operating system
114 supports this. For example, recent versions of the Linux kernel
115 support setting times on symlinks, and some BSD kernels also support
118 ** --dereference consistency
120 The --dereference (-h) option now applies to files that are copied
121 into or out of archives, independently of other options. For example,
122 if F is a symbolic link and archive.tar contains a regular-file member
123 also named F, "tar --overwrite -x -f archive.tar F" now overwrites F
124 itself, rather than the file that F points to. (To overwrite the file
125 that F points to, add the --dereference (-h) option.) Formerly,
126 --dereference was intended to apply only when using the -c option, but
127 the implementation was not consistent.
129 Also, the --dereference option no longer affects accesses to other
130 files, such as archives and time stamp files. Symbolic links to these
131 files are always followed. Previously, the links were usually but not
134 ** Spurious error diagnostics on broken pipe.
136 When receiving SIGPIPE, tar would exit with error status and
137 "write error" diagnostics. In particular, this occurred if
138 invoked as in the example below:
140 tar tf archive.tar | head -n 1
144 'tar --remove-files' failed to remove a directory which contained
145 symlinks to another files within that directory.
147 ** --test-label behavior
149 In case of a mismatch, 'tar --test-label LABEL' exits with code 1,
150 not 2 as it did in previous versions.
152 The '--verbose' option used with '--test-label' provides additional
155 Several volume labels may be specified in a command line, e.g.:
157 tar --test-label -f archive 'My volume' 'New volume' 'Test volume'
159 In this case, tar exits with code 0 if any one of the arguments
160 matches the actual volume label.
162 ** --label used with --update
164 The '--label' option can be used with '--update' to prevent accidental
165 update of an archive:
167 tar -rf archive --label 'My volume' .
169 This did not work in previous versions, in spite of what the docs said.
171 ** --record-size and --tape-length (-L) options
173 Usual size suffixes are allowed for these options. For example,
174 -L10k stands for a 10 kilobyte tape length.
176 ** Fix dead loop on extracting existing symlinks with the -k option.
179 version 1.23 - Sergey Poznyakoff, 2010-03-10
181 * Record size autodetection
183 When listing or extracting archives, the actual record size is
184 reported only if the archive is read from a device (as opposed
185 to regular files and pipes).
189 When a read-only operation (e.g. --list or --extract) is requested
190 on a regular file, tar attemtps to speed up accesses by using lseek.
192 * New command line option '--warning'
194 The '--warning' command line option allows to suppress or enable
195 particular warning messages during 'tar' run. It takes a single
196 argument (a 'keyword'), identifying the class of warning messages
197 to affect. If the argument is prefixed with 'no-', such warning
198 messages are suppressed. For example,
200 tar --warning=no-alone-zero-block -x -f archive
202 suppresses the output of "A lone zero block" diagnostics, which is
203 normally issued if 'archive' ends with a single block of zeros.
205 See Tar Manual, section 3.9 "Controlling Warning Messages", for a
208 * New command line option '--level'
210 The '--level=N' option sets the incremental dump level N. It
211 is valid when used in conjunction with the -c and --listed-incremental
212 options. So far the only meaningful value for N is 0. The
213 '--level=0' option forces creating the level 0 dump, by truncating
214 the snapshot file if it exists.
216 * Files removed during incremental dumps
218 If a file or directory is removed while incremental dump is
219 in progress, tar exact actions depend on whether this file
220 was explicitly listed in the command line, or was found
221 during file system scan.
223 If the file was explicitly listed in the command line, tar
224 issues error message and exits with the code 2, meaning
227 Otherwise, if the file was found during the file system scan,
228 tar issues a warning, saying "File removed before we read it",
229 and sets exit code to 1, which means "some files differ".
230 If the --warning=no-file-removed option is given, no warning
231 is issued and exit code remains 0.
233 * Modification times of PAX extended headers.
235 Modification times in ustar header blocks of extended headers
236 are set to mtimes of the corresponding archive members. This
237 can be overridden by the
239 --pax-opion='exthdr.mtime=STRING'
241 command line option. The STRING is either number of seconds since
242 the Epoch or a "Time reference" (see below).
244 Modification times in ustar header blocks of global extended
245 headers are set to the time when tar was invoked.
247 This can be overridden by the
249 --pax-opion='globexthdr.mtime=STRING'
251 command line option. The STRING is either number of seconds since
252 the Epoch or a "Time reference" (see below).
254 * Time references in --pax-option argument.
256 Any value from the --pax-option argument that is enclosed in a pair
257 of curly braces represents a time reference. The string between the
258 braces is understood either as a textual time representation, as described in
259 chapter 7, "Date input formats", of the Tar manual, or as a name of
260 an existing file, starting with '/' or '.'. In the latter
261 case, it is replaced with the modification time of that file.
263 * Environment of --to-command script.
265 The environment passed to the --to-command script is extended with
266 the following variables:
268 TAR_VERSION GNU tar version number
269 TAR_ARCHIVE The name of the archive
270 TAR_VOLUME Ordinal number of the volume
271 TAR_FORMAT Format of the archive
272 TAR_BLOCKING_FACTOR Current blocking factor
275 ** Fix handling of hard link targets by -c --transform.
276 ** Fix hard links recognition with -c --remove-files.
277 ** Fix restoring files from backup (debian bug #508199).
278 ** Correctly restore modes and permissions on existing directories.
279 ** The --remove-files option removes files only if they were
280 succesfully stored in the archive.
281 ** Fix storing and listing of the volume labels in POSIX format.
282 ** Improve algorithm for splitting long file names (ustar
284 ** Fix possible memory overflow in the rmt client code (CVE-2010-0624).
287 version 1.22 - Sergey Poznyakoff, 2009-03-05
289 * Support for xz compression
291 Tar uses xz for compression if one of the following conditions is met:
293 1. The option --xz or -J (see below) is used.
294 2. The xz binary is set as compressor using --use-compress-program option.
295 3. The file name of the archive being created ends in '.xz' and
296 auto-compress option (-a) is used.
298 Xz is used for decompression if one of the following conditions is met:
300 1. The option --xz or -J is used.
301 2. The xz binary is set as compressor using --use-compress-program option.
302 3. The file is recognized as xz compressed stream data.
304 * Short option -J reassigned as a short equivalent of --xz
308 The -I option is assigned as a short equivalent for
309 --use-compress-program.
311 * The --no-recursive option works in incremental mode.
314 version 1.21 - Sergey Poznyakoff, 2008-12-27
316 * New short option -J
318 A shortcut for --lzma.
322 * New option --no-auto-compress
324 Cancels the effect of previous --auto-compress (-a) option.
326 * New option --no-null
328 Cancels the effect of previous --null option.
330 * Compressed format recognition
332 If tar is unable to determine archive compression format, it falls
333 back to using archive suffix to determine it.
337 Using --exclude-vcs handles also files used internally by Bazaar,
340 * Transformation scope flags
342 Name transformation expressions understand additional flags that
343 control type of archive members affected by them. The flags are:
346 Apply transformation to regular archive members.
349 Apply transformation to symbolic link targets.
352 Apply transformation to hard link targets.
354 Corresponding upper-case letters negate the meaning, so that
355 'H' means "do not apply transformation to hard link targets".
357 The scope flags are listed in the third part of an 's' expression,
360 tar --transform 's|^|/usr/local/|S'
362 Default is 'rsh', which means that transformations are applied to
363 both regular archive members and to the targets of symbolic and hard
364 links. If several transform expressions are used, the default flags
365 can be changed using 'flags=' statement before the expressions, e.g.:
367 tar --transform 'flags=S;s|^|/usr/local/|S'
371 ** The --null option disabled handling of tar options in list files. This
373 ** Fixed record size autodetection. If the detected record size differs from
374 the expected value (either default one, or the one set from the
375 command line), tar always prints a warning if verbosity level is set
376 to 1 or greater, i.e. if either -t or -v option is given.
380 version 1.20 - Sergey Poznyakoff, 2008-04-14
382 * New option --auto-compress (-a)
384 With --create, selects compression algorithm basing on the suffix
385 of the archive file name.
389 Selects LZMA compression algorithm
391 * New option --hard-dereference
393 During archive creation, dereferences hard links and stores the files
394 they refer to, instead of creating usual hard link members (type '1').
396 * New option --checkpoint-action
398 This action allows to specify an action to be executed upon hitting a
399 checkpoint. Recognized actions are: dot, echo (the default),
400 echo=string, ttyout=string, exec=cmdline, and sleep=value. Any number
401 of '--checkpoint-action' options can be specified, the actions will be
402 executed in order of their appearance in the command line. See
403 chapter 3.8 "Checkpoints" for a complete description.
405 * New options --no-check-device, --check-device.
407 The '--no-check-device' option disables comparing device numbers during
408 preparatory stage of an incremental dump. This allows to avoid
409 creating full dumps if the device numbers change (e.g. when using an
412 The '--check-device' option enables comparing device numbers. This is
413 the default. This option is provided to undo the effect of the previous
414 '--no-check-device' option, e.g. if it was set in TAR_OPTIONS
415 environment variable.
417 * The --transform option.
419 Any number of '--transform' options can be given in the command line.
420 The specified transformations will be applied in turn.
422 The argument to '--transform' option can be a list of replace
423 expressions, separated by a semicolon (as in 'sed').
425 Filename transformations are applied to symbolic link targets
426 during both creation and extraction. Tar 1.19 used them only
429 For a detailed description, see chapter 6.7 "Modifying File and Member
432 * Info (end-of-volume) scripts
434 The value of the blocking factor is made available to info and
435 checkpoint scripts via environment variable TAR_BLOCKING_FACTOR.
437 * Incremental archives
439 Improved (sped up) extracting from incremental archives.
442 ** Fix bug introduced in version 1.19: tar refused to update non-existing
446 version 1.19 - Sergey Poznyakoff, 2007-10-10
448 * New option --exclude-vcs
450 Excludes directories and files, created by several widely used version
451 control systems, e.g. "CVS/", ".svn/", etc.
453 * --exclude-tag and --exclude-cache options
455 The following options now work with incremental archives as well:
463 * Fix handling of renamed files in listed incremental archives.
465 Previous versions always stored absolute file names in rename
466 records, even if -P was not used. This is fixed: rename records
467 contain file names processed in accordance with the command line
470 * Fix --version output.
472 * Recognition of broken archives.
474 When supplied an archive smaller than 512 bytes in reading mode (-x,
475 -t), the previous version of tar silently ignored it, exiting with
476 code 0. It is fixed. Tar now issues the following diagnostic message:
477 'This does not look like a tar archive', and exits with code 2.
479 * Fix double-dot recognition in archive member names in case of duplicate '/.'.
481 * Fix file padding in case of truncation of the input file to zero size.
484 version 1.18 - Sergey Poznyakoff, 2007-06-29
486 * Licensed under the GPLv3
488 * Fixed several bugs in the testsuite
491 version 1.17 - Sergey Poznyakoff, 2007-06-08
493 * Fix archivation of sparse files in posix mode. Previous versions padded
494 sparse members with spurious zero blocks.
496 * Fix operation of --verify --listed-incremental. Version 1.16.1 produced
497 a full dump when both options were given.
499 * Fix --occurrence. In previous versions it continued scanning the archive
500 even though all requested members has already been extracted.
502 * Scope of --transform and --strip-components options.
504 In addition to affecting regular archive members, the --transform
505 option affects hard and soft link targets and the --strip-components
506 option affects hard link targets as well.
508 * End-of-volume script can send the new volume name to tar by writing
509 it to the file descriptor stored in the environment variable TAR_FD.
512 version 1.16.1 - Sergey Poznyakoff, 2006-12-09
514 * New option --exclude-tag allows to specify "exclusion tag files", i.e.
515 files whose presence in a directory means that the directory should not
518 * The --exclude-cache option excludes directories that contain the
519 CACHEDIR.TAG file from being archived. Previous versions excluded
520 directory contents only, while the directories themselves were
521 still added to the archive.
523 * Support for reading ustar type 'N' header logical records has been removed.
524 This GNU extension was generated only by very old versions of GNU 'tar'.
525 Unfortunately its implementation had security holes; see
526 <http://archives.neohapsis.com/archives/fulldisclosure/2006-11/0344.html>.
527 We don't expect that any tar archives in practical use have type 'N'
528 records, but if you have one and you trust its contents, you can
529 decode it with GNU tar 1.16 or earlier.
531 * Race conditions have been fixed that in some cases briefly allowed
532 files extracted by 'tar -x --same-owner' (or plain 'tar -x', when
533 running as root) to be accessed by users that they shouldn't have been.
536 version 1.16 - Sergey Poznyakoff, 2006-10-21
538 * After creating an archive, tar exits with code 1 if some files were
539 changed while being read. Previous versions exited with code 2 (fatal
540 error), and only if some files were truncated while being archived.
542 * New option --mtime allows to set modification times for all archive
543 members during creation.
546 ** Avoid running off file descriptors when using multiple -C options.
547 ** tar --index-file=FILE --file=- sent the archive to FILE, and
548 the listing to stderr.
551 version 1.15.91 - Sergey Poznyakoff, 2006-06-16
553 * Incompatible changes
557 Previous versions of GNU tar assumed shell-style globbing when
558 extracting from or listing an archive. For example:
562 would extract all files whose names end in '.c'. This behavior
563 was not documented and was incompatible with traditional tar
564 implementations. Therefore, starting from this version, GNU tar
565 no longer uses globbing by default. For example, the above invocation
566 is now interpreted as a request to extract from the archive the file
569 To treat member names as globbing patterns, use --wildcards option.
570 If you wish tar to mimic the behavior of versions up to 1.15.90,
571 add --wildcards to the value of the environment variable TAR_OPTIONS.
573 The exact way in which tar interprets member names is controlled by the
574 following command line options:
576 --wildcards use wildcards
577 --anchored patterns match file name start
578 --ignore-case ignore case
579 --wildcards-match-slash wildcards match '/'
581 Each of these options has a '--no-' counterpart that disables its
582 effect (e.g. --no-wildcards).
584 These options affect both the interpretation of member names from
585 command line and that of the exclusion patterns (given with --exclude
586 and --exclude-from options). The defaults are:
588 1. For member names: --no-wildcards --anchored
589 2. For exclusion patterns: --wildcards --no-anchored --wildcards-match-slash
591 The options can appear multiple times in the command line, thereby
592 changing the way command line arguments are interpreted. For example,
593 to use case-insensitive matching in exclude patterns and to revert to
594 case-sensitive matching for the rest of command line, one could write:
596 tar xf foo.tar --ignore-case --exclude-from=FILE --no-ignore-case file.name
598 ** Short option -l is now an alias of --check-links option, which complies
599 with UNIX98. This ends the transition period started with version 1.14.
603 ** New option --transform allows to transform file names before storing them
604 in the archive or member names before extracting. The option takes a
605 sed replace expression as its argument. For example,
607 tar cf foo.tar --transform 's,^,prefix/,'
609 will add 'prefix/' to all file names stored in foo.tar.
611 ** --strip-components option works when deleting and comparing. In previous
612 versions it worked only with --extract.
614 ** New option --show-transformed-names enables display of transformed file
615 or archive. It generalizes --show-stored-names option, introduced in
616 1.15.90. In particular, when creating an archive in verbose mode, it lists
617 member names as stored in the archive, i.e., with any eventual prefixes
618 removed and file name transformations applied. The option is useful,
619 for example, while comparing 'tar cv' and 'tar tv' outputs.
621 ** New incremental snapshot file format keeps information about file names
622 as well as that about directories.
624 ** The --checkpoint option takes an optional argument specifying the number
625 of records between the two successive checkpoints. Optional dot
626 starting the argument intructs tar to print dots instead of textual
629 ** The --totals option can be used with any tar operation (previous versions
630 understood it only with --create). If an argument to this option is
631 given, it specifies the signal upon delivery of which the statistics
632 is to be printed. Both forms of this option (with and without
633 argument) can be given to in a single invocation of tar.
636 ** Detect attempts to update compressed archives.
639 version 1.15.90 - Sergey Poznyakoff, 2006-02-19
643 ** Any number of -T (--files-from) options may be used in the command line.
644 The file specified with -T may include any valid 'tar' options,
645 including another -T option.
646 Compatibility note: older versions of tar would only recognize -C
647 as an option name within the file list file. Now any file whose name
648 starts with - is handled as an option. To insert file names starting with
649 dash, use the --add-file option.
651 ** List files containing null-separated file names are detected and processed
652 automatically. It is no longer necessary to give the --null option.
654 ** New option --no-unquote disables the unquoting of input file names.
655 This is useful for processing output from 'find dir -print0'.
656 An orthogonal option --unquote is provided as well.
658 ** New option --test-label tests the archive volume label.
659 If an argument is specified, the label is compared against its value.
660 Tar exits with code 0 if the two strings match, and with code 2 if
663 If no argument is given, the --verbose option is implied. In this case,
664 tar prints the label name if present and exits with code 0.
666 ** New option --show-stored-names. When creating an archive in verbose mode,
667 it lists member names as stored in the archive, i.e., with any eventual
668 prefixes removed. The option is useful, for example, while comparing
669 'tar cv' and 'tar tv' outputs.
671 ** New option --to-command pipes the contents of archive members to the
674 ** New option --atime-preserve=system, which uses the O_NOATIME feature
675 of recent Linux kernels to avoid some problems when preserving file
678 ** New option --delay-directory-restore delays restoring modification times
679 and permissions of extracted directories until the end of extraction.
680 This is necessary for restoring from archives with unusual member
681 ordering (in particular, those created with --no-recursion option).
682 This option is implied when restoring from incremental archives.
684 ** New option --restrict prohibits use of some potentially harmful tar
685 options. Currently it disables '!' escape in multi-volume name menu.
687 ** New options --quoting-style and --quote-chars control the way tar
688 quotes member names on output. The --quoting-style takes an argument
689 specifying the quoting style to use (literal, shell, shell-always,
690 c, escape, locale, clocale). The argument to --quote-chars is a string
691 specifying characters to quote, even if the selected quoting style
692 would not quote them otherwise. The option --no-quote-chars is
693 provided to disable quoting certain characters.
695 ** The end-of-volume script (introduced with --info-script option) can
696 get current archive name from the environment variable TAR_ARCHIVE and
697 the volume number from the variable TAR_VOLUME. It can alter the
698 archive name by writing new name to the file descriptor 3.
700 ** Better support for full-resolution time stamps. Tar cannot restore
701 time stamps to full nanosecond resolution, though, until the kernel
702 guys get their act together and give us a system call to set file time
703 stamps to nanosecond resolution.
705 ** The -v option now prints time stamps only to 1-minute resolution,
706 not full resolution, to avoid using up too many output columns.
707 Nanosecond resolution is now supported, but that would be too much.
711 ** Allow non-option arguments to be interspersed with options.
712 ** When extracting or listing archives in old GNU format, tar
713 used to read an extra block of data after a long name header
714 if length of the member name was divisible by block size (512).
715 Consequently, the file pointer was set off and the next member
716 was not processed correctly.
717 ** Previous version created invalid archives when files shrink
719 ** Compare mode (tar d) hung when trying to compare file contents.
720 ** Previous versions in certain cases failed to restore directory
722 ** When creating an archive, do not attempt to store files whose
723 meta-data cannot be stored in the header due to format limitations
724 (for ustar and v7 formats).
725 ** The --version option now also outputs information about copyright,
726 license, and credits. This reverts to the behavior of tar 1.14 and
727 earlier, and conforms to the GNU coding standards. The --license (-L)
728 option introduced in tar 1.15 has been removed, since it's no longer
732 version 1.15.1 - Sergey Poznyakoff, 2004-12-21
734 This version fixes a bug introduced in 1.15 which caused
735 tar to refuse to extract files from standard input.
738 version 1.15 - Sergey Poznyakoff, 2004-12-20
740 * Compressed archives are recognised automatically, it is no longer
741 necessary to specify -Z, -z, or -j options to read them. Thus, you can
742 now run 'tar tf archive.tar.gz'.
744 * When restoring incremental dumps, --one-file-system option
745 prevents directory hierarchies residing on different devices
748 With the previous versions of tar it was dangerous to create
749 incremental dumps with --one-file-system option, since they
750 would recursively remove mount points when restoring from the
751 back up. This change fixes the bug.
753 * Renamed --strip-path to --strip-components for consistency with
756 * Skipping archive members is sped up if the archive media supports
759 * Restore script starts restoring only if it is given --all (-a) option,
760 or some patterns. This is to prevent accidental restores.
762 * 'tar --verify' prints a warning if during archive creation some of
763 the file names had their prefixes stripped off.
765 * New option --exclude-caches instructs tar to exclude cache directories
766 automatically on archive creation. Cache directories are those
767 containing a standardized tag file, as specified at:
769 http://www.brynosaurus.com/cachedir/spec.html
771 * New configure option --with-rmt allows to specify full path name to
772 the 'rmt' utility. This supersedes DEFAULT_RMT_COMMAND variable
773 introduced in version 1.14
775 * New configure variable DEFAULT_RMT_DIR allows to specify the directory
776 where to install 'rmt' utility. This is necessary since modifying
777 --libexecdir as was suggested for version 1.14 produced a side effect: it
778 also modified installation prefix for backup scripts (if
779 --enable-backup-scripts was given).
782 ** Fixed flow in recognizing files to be included in incremental dumps.
783 ** Correctly recognize sparse archive members when used with -T option.
784 ** GNU multivolume headers cannot store filenames longer than 100 characters.
785 Do not allow multivolume archives to begin with such filenames.
786 ** If a member with link count > 2 was stored in the archive twice,
787 previous versions of tar were not able to extract it, since they
788 were trying to link the file to itself, which always failed and
789 lead to removing the already extracted copy. Preserve the first
790 extracted copy in such cases.
791 ** Restore script was passing improper argument to tar --listed option (which
792 didn't affect the functionality, but was logically incorrect).
793 ** Fixed verification of created archives.
794 ** Fixed unquoting of file names containing backslash escapes (previous
795 versions failed to recognize \a and \v).
796 ** When attempting to delete a non-existing member from the archive, previous
797 versions of tar used to overwrite last archive block with zeroes.
800 version 1.14 - Sergey Poznyakoff, 2004-05-11
802 * Added support for POSIX.1-2001 and ustar archive formats.
803 * New option --format allows to select the output archive format
804 * The default output format can be selected at configuration time
805 by presetting the environment variable DEFAULT_ARCHIVE_FORMAT.
806 Allowed values are GNU, V7, OLDGNU and POSIX.
807 * New option --strip-path allows to cut off a given number of
808 path elements from the name of the file being extracted.
810 * New options --index-file, --no-overwrite-dir. The --overwrite-dir
811 option is now the default; use --no-overwrite-dir if you prefer
812 the previous default behavior.
814 * The semantics of -o option is changed. When extracting, it
815 does the same as --no-same-owner GNU tar option. This is compatible
816 with UNIX98 tar. Otherwise, its effect is the same as that of
817 --old-archive option. This latter is deprecated and will be removed
820 * New option --check-links prints a message if not all links are dumped
821 for a file being archived. This corresponds to the UNIX98 -l option.
822 The current semantics of the -l option is retained for compatibility
823 with previous releases, however such usage is strongly deprecated as
824 the option will change to its UNIX98 semantics in the future releases.
826 * New option --occurrence[=N] can be used in conjunction with one of
827 the subcommands --delete, --diff, --extract or --list when a list of
828 files is given either on the command line or via -T option. This
829 option instructs tar to process only the Nth occurrence of each named
830 file. N defaults to 1, so 'tar -x -f archive --occurrence filename'
831 extracts the first occurrence of 'filename' from 'archive'
832 and terminates without scanning to the end of the archive.
834 * New option --pax-option allows to control the handling of POSIX
835 keywords in 'pax' extended headers. It is equivalent to 'pax'
838 * --incremental and --listed-incremental options work correctly on
839 individual files, as well as on directories.
841 * New scripts: backup (replaces old level-0 and level-1) and restore.
842 The scripts are compiled and installed if --enable-backup-scripts
843 option is given to configure.
845 * By default tar searches "rmt" utility in "$prefix/libexec/rmt",
846 which is consistent with the location where the version of "rmt"
847 included in the package is installed. Previous versions of tar
848 used "/etc/rmt". To install "rmt" to its traditional location,
849 run configure with option --libexecdir=/etc. Otherwise, if you
850 already have rmt installed and wish to use it, instead of the
851 shipped in version, set the variable DEFAULT_RMT_COMMAND to
852 the full path name of the utility, e.g., ./configure
853 DEFAULT_RMT_COMMAND=/etc/rmt.
855 Notice also that the full path name of the "rmt" utility to
856 use can be set at runtime, by giving option --rmt-command to
859 * Removed obsolete command line options:
860 ** --absolute-paths superseded by --absolute-names
861 ** --block-compress is not needed any longer
862 ** --block-size superseded by --blocking-factor
863 ** --modification-time superseded by --touch
864 ** --read-full-blocks superseded by --read-full-records
865 ** --record-number superseded by --block-number
866 ** --version-control superseded by --backup
868 * New message translations fi (Finnish), gl (Galician), hr (Croatian),
869 hu (Hungarian), ms (Malaysian), nb (Norwegian), ro (Romanian), sk
870 (Slovak), zh_CN (Chinese simplified), zh_TW (Chinese traditional).
871 The code 'no' for Norwegian (Bokmål) has been withdrawn; use 'nb' instead.
876 version 1.13.25 - Paul Eggert, 2001-09-26
881 version 1.13.24 - Paul Eggert, 2001-09-22
883 * New option --overwrite-dir.
884 * Fixes for buffer overrun, porting, and copyright notice problems.
885 * The message translations for Korean are available again.
888 version 1.13.23 - Paul Eggert, 2001-09-13
890 * Bug, porting, and copyright notice fixes.
893 version 1.13.22 - Paul Eggert, 2001-08-29
898 version 1.13.21 - Paul Eggert, 2001-08-28
900 * Porting and copyright notice fixes.
903 version 1.13.20 - Paul Eggert, 2001-08-27
905 * Some bugs were fixed:
907 - hard links to symbolic links
909 * New option --recursion (the default) that is the inverse of --no-recursion.
911 * New options --anchored, --ignore-case, --wildcards,
912 --wildcards-match-slash, and their negations (e.g., --no-anchored).
913 Along with --recursion and --no-recursion, these options control how
914 exclude patterns are interpreted.
916 * The default interpretation of exclude patterns is now --no-anchored
917 --no-ignore-case --recursion --wildcards --wildcards-match-slash.
918 This is a quiet change to the semantics of --exclude. The previous
919 semantics were a failed attempt at backward compatibility but it
920 became clear that the semantics were puzzling and did not satisfy
921 everybody. Rather than continue to try to revive that dead horse we
922 thought it better to substitute cleaner semantics, with options so
923 that you can change the behavior more to your liking.
925 * New message translations for Indonesian and Turkish.
926 The translation for Korean has been withdrawn due to encoding errors.
927 It will be reissued once those are fixed.
930 version 1.13.19 - Paul Eggert, 2001-01-13
932 * The -I option has been withdrawn, as it was buggy and confusing.
933 Eventually it is planned to be reintroduced, with the same meaning as -T.
935 * With an option like -N DATE, if DATE starts with "/" or ".", it is taken
936 to be a file name; the last-modified time of that file is used as the date.
939 version 1.13.18 - Paul Eggert, 2000-10-29
941 * Some security problems have been fixed. 'tar -x' now modifies only
942 files under the working directory, unless you also specify an unsafe
943 option like --absolute-names or --overwrite.
945 * The short name of the --bzip option has been changed to -j,
946 and -I is now an alias for -T, for compatibility with Solaris tar.
948 * The manual is now distributed under the GNU Free Documentation License.
950 * The new environment variable TAR_OPTIONS holds default command-line options.
952 * The --no-recursion option now affects extraction too.
954 * The wording in some diagnostics has been changed slightly.
956 * Snapshot files now record whether each file was accessed via NFS.
957 The new file format is upward- and downward-compatible with the old.
959 * New language supported: da.
961 * Compilation by traditional (K&R) C compilers is no longer supported.
962 If you still use such a compiler, please use GCC instead.
964 * This version of tar works best with GNU gzip test version 1.3 or later.
965 Please see <ftp://alpha.gnu.org/gnu/gzip/>.
967 * 'tar --delete -f -' now works again.
970 version 1.13.17 - Paul Eggert, 2000-01-07.
972 * 'tar --delete -f -' is no longer allowed; it was too buggy.
973 * Diagnostic messages have been made more regular and consistent.
976 version 1.13.16 - Paul Eggert, 1999-12-13.
978 * By default, tar now refuses to overwrite an existing file when
979 extracting files from an archive; instead, it removes the file
980 before extracting it. If the existing file is a symbolic link, the
981 link is removed and not the pointed-to file. There is one
982 exception: existing nonempty directories are not removed, nor are
983 their ownerships or permissions extracted. This fixes some
984 longstanding security problems.
986 The new --overwrite option enables the old default behavior.
988 For regular files, tar implements this change by using the O_EXCL
989 option of 'open' to ensure that it creates the file; if this fails, it
990 removes the file and tries again. This is similar to the behavior of
991 the --unlink-first option, but it is faster in the common case of
992 extracting a new directory.
994 * By default, tar now ignores file names containing a component of '..'
995 when extracting, and warns about such file names when creating an archive.
996 To enable the old behavior, use the -P or --absolute-names option.
998 * Tar now handles file names with multibyte encodings (e.g., UTF-8, Shift-JIS)
999 correctly. It relies on the mbrtowc function to handle multibyte characters.
1001 * The file generated by -g or --listed-incremental now uses a format
1002 that is independent of locale, so that users need not worry about
1003 locale when restoring a backup. This is needed for proper support
1004 of multibyte characters. Old-format files can still be read, and
1005 older versions of GNU tar can read new-format files, unless member
1006 names have multibyte chars.
1008 * Many diagnostics have been changed slightly, so that file names are
1009 now output unambiguously. File names in diagnostics now are either
1010 `quoted like this' (in the default C locale) or are followed by
1011 colon, newline, or space, depending on context. Unprintable
1012 characters are escaped with a C-like backslash conventions.
1013 Terminating characters (e.g., close-quote, colon, newline)
1014 are also escaped as needed.
1016 * tar now ignores socket files when creating an archive.
1017 Previously tar archived sockets as fifos, which caused problems.
1020 version 1.13.15 - Paul Eggert, 1999-12-03.
1022 * If a file's ctime changes when being archived, report an error.
1023 Previously tar looked at mtime, which missed some errors.
1026 version 1.13.14 - Paul Eggert, 1999-11-07.
1028 * New translations ja, pt_BR.
1029 * New options --help and --version for rmt.
1030 * Ignore Solaris door files when creating an archive.
1033 version 1.13.13 - Paul Eggert, 1999-10-11.
1035 * Invalid headers in tar files now elicit errors, not just warnings.
1036 * 'tar --version' output conforms to the latest GNU coding standards.
1037 * If you specify an invalid date, 'tar' now substitutes (time_t) -1.
1038 * 'configure --with-dmalloc' is no longer available.
1041 version 1.13.12 - Paul Eggert, 1999-09-24.
1043 * 'tar' now supports hard links to symbolic links.
1045 * New options --no-same-owner, --no-same-permissions.
1047 * --total now also outputs a human-readable size, and a throughput value.
1049 * 'tar' now uses two's-complement base-256 when outputting header
1050 values that are out of the range of the standard unsigned base-8
1051 format. This affects archive members with negative or huge time
1052 stamps or uids, and archive members 8 GB or larger. The new tar
1053 archives cannot be read by traditional tar, or by older versions of
1054 GNU tar. Use the --old-archive option to revert to the old
1055 behavior, which uses unportable representations for negative values,
1056 and which rejects large files.
1058 * On 32-bit hosts, 'tar' now assumes that an incoming time stamp T in
1059 the range 2**31 <= T < 2**32 represents the negative time (T -
1060 2**32). This behavior is nonstandard and is not portable to 64-bit
1061 time_t hosts, so 'tar' issues a warning.
1063 * 'tar' no longer gives up extracting immediately upon discovering
1064 that an archive contains garbage at the end. It attempts to extract
1065 as many files as possible from the good data before the garbage.
1067 * A read error now causes a nonzero exit status, not just a warning.
1069 * Some diagnostics have been reworded for consistency.
1072 version 1.13.11 - Paul Eggert, 1999-08-23.
1074 * The short name of the --bzip option has been changed to -I,
1075 for compatibility with paxutils.
1077 * -T /dev/null now matches nothing; previously, it matched anything
1078 if no explicit operands were given.
1080 * The '--' option now works the same as with other GNU utilities;
1081 it causes later operands to be interpreted as file names, not options,
1082 even if they begin with '-'.
1084 * For the --newer and --after-date options, the table of time zone
1085 abbreviations like 'EST' has been updated to match current practice.
1086 Also, local time abbreviations are now recognized, even if they are
1087 not in tar's hardwired table. Remember, though, that you should use
1088 numeric UTC offsets like '-0500' instead of abbreviations like
1089 'EST', as abbreviations are not standardized and are ambiguous.
1092 version 1.13.10 - Paul Eggert, 1999-08-20.
1094 * 'tar' now uses signed base-64 when outputting header values that are
1095 out of the range of the standard unsigned base-8 format. [This
1096 change was superseded in 1.13.12, described above.]
1099 version 1.13.9 - Paul Eggert, 1999-08-18.
1101 * 'tar' now writes two zero blocks at end-of-archive instead of just one.
1102 POSIX.1 requires this, and some other 'tar' implementations check for it.
1104 * 'tar' no longer silently accepts a block containing nonzero checksum bytes
1107 * 'tar' now reads buggy tar files that have a null byte at the start of a
1108 numeric header field.
1111 version 1.13.8 - Paul Eggert, 1999-08-16.
1113 * For compatibility with traditional 'tar', intermediate directories
1114 created automatically by root are no longer given the uid and gid of
1115 the original file or directory.
1118 version 1.13.7 - Paul Eggert, 1999-08-14.
1120 * --listed-incremental and --newer are now incompatible options.
1122 * When creating an archive, leading './' is no longer stripped,
1123 to match traditional tar's behavior (and simplify the documentation).
1125 * --diff without --absolute-names no longer falls back on absolute names.
1128 version 1.13.6 - Paul Eggert, 1999-08-11.
1130 * An --exclude pattern containing / now excludes a file only if it matches an
1131 initial prefix of the file name; a pattern without / continues to
1132 exclude a file if it matches any file name component.
1134 * The protocol for talking to rmt has been extended slightly.
1135 Open flags are now communicated in symbolic format as well as numeric.
1136 The symbolic format (e.g., "O_WRONLY|O_CREAT|O_TRUNC") is for portability
1137 when rmt is operating on a different operating system from tar.
1138 The numeric format is retained, and rmt uses it if symbolic format is absent,
1139 for backward compatibility with older versions of tar and rmt.
1141 * When writing GNU tar format headers, tar now uses signed base-64
1142 for values that cannot be represented in unsigned octal.
1143 This supports larger files (2**66 - 1 bytes instead of 2**33 - 1 bytes),
1144 larger uids, negative time stamps, etc.
1146 * When extracting files with unknown ownership, tar now looks up the
1147 uid and gid "nobody" on hosts whose headers do not define UID_NOBODY
1148 and GID_NOBODY, and falls back on uid/gid -2 if there is no "nobody".
1150 * tar -t --numeric-owner now prints numeric uids and gids, not symbolic.
1152 * New option -y or --bzip2 for bzip2 compression, by popular request.
1155 version 1.13.5 - Paul Eggert, 1999-07-20.
1157 * Do the delayed updates of file metadata even after a fatal error.
1160 version 1.13.4 - Paul Eggert, 1999-07-20.
1162 * Do not chmod unless we are root or the -p option was given;
1163 this matches historical practice.
1166 version 1.13.3 - Paul Eggert, 1999-07-16.
1168 * A path name is excluded if any of its file name components matches an
1169 excluded pattern, even if the path name was specified on the command line.
1170 Also see 1.13.6 for later changes in this area.
1173 version 1.13.2 - Paul Eggert, 1999-07-14.
1175 * Bug reporting address changed to <bug-tar@gnu.org>.
1178 version 1.13.1 - Paul Eggert, 1999-07-12.
1182 version 1.13 - Paul Eggert, 1999-07-08.
1184 * Support for large files, e.g., files larger than 2 GB on many 32-bit hosts.
1185 Also, support for larger uids, device ids, etc.
1186 * Many bug fixes and porting fixes.
1187 * This release is only for fixes. A more ambitious test release,
1188 with new features, is available as part of the paxutils. Please see:
1189 ftp://alpha.gnu.org/gnu/paxutils/
1190 The fixes in this release are intended to be merged with paxutils
1191 at some point, but they haven't been merged yet.
1192 * An interim GNU tar alpha had new --bzip2 and --ending-file options,
1193 but they have been removed to maintain compatibility with paxutils.
1194 Please try --use=bzip2 instead of --bzip2.
1196 Version 1.12 - François Pinard, 1997-04.
1199 * Use shell globbing patterns for --label, instead of regular expressions.
1200 * Do not quote anymore internally over the quoting done by the shell.
1203 * Offer internationalization capabilities of most recent GNU gettext.
1204 * Messages available in many more languages, thanks to all translators!
1205 * Usage of ISO 8601 dates in listings, instead of local American dates.
1206 * More normalization and cleanup in error messages.
1209 * For helping using tar with find, offer a --no-recursion option.
1210 * Implement --numeric-owner for ignoring symbolic names at create time.
1211 * New --owner, --group --mode options, still preliminary.
1212 * Recognize creating an archive on /dev/null, so Amanda works faster.
1213 * Object to the creation of an empty archive (like in 'tar cf FILE').
1214 * Barely start implementing --posix and POSIXLY_CORRECT.
1217 * Make a better job at restoring file and directory attributes.
1218 * Automatically attempt deleting existing files when in the way.
1219 * Option --unlink-first (-U) removes most files prior to extraction.
1220 * Option --recursive-unlink removes non-empty directories when in the way.
1221 * Option --numeric-owner ignores owner/group names, it uses UID/GID instead.
1222 * Use global umask when creating missing intermediate directories.
1223 * When symlinks are not available, extract symbolic links as hard links.
1224 * Diagnose extraction of contiguous files as regular files.
1225 * New --backup, --suffix and --version-control options.
1228 * Better support of huge archives with --tape-length and --totals.
1229 * Rename option --read-full-blocks (-B) to --read-full-records (-B).
1230 * Rename option --block-size (-b) to --blocking-factor (-b).
1231 * Rename option --record-number (-R) to --block-number (-R).
1232 * With --block-number (-R), report null blocks and end of file.
1233 * Implement --record-size for introducing a size in bytes.
1234 * Delete --block-compress option and rather decide it automatically.
1235 * Rename option --modification-time to --touch.
1237 Many bugs are squashed, while others still run free.
1239 Version 1.11.8 - François Pinard, 1995-06.
1241 * Messages available in French, German, Portuguese and Swedish.
1242 * The distribution provides a rudimentary Texinfo manual.
1243 * The device defaults to stdin/stdout, unless overridden by the installer.
1244 * Option --sparse (-S) should work on more systems.
1245 * Option --rsh-command may select an alternative remote shell program.
1247 Most changes are internal, and should yield better portability.
1249 Version 1.11.2 - Michael Bushnell, 1993-03.
1251 * Changes in backup scripts: cleaned up considerably; notices error
1252 conditions better over rsh; DUMP_REMIND_SCRIPT is now an option in
1253 backup-specs; new file dump-remind is an example of a
1256 * Superfluous "Reading dirname" was a bug; fixed.
1258 * Incompatibility problems with a bug on Solaris are fixed.
1260 * New option --gzip (aliases are --ungzip and -z); calls gzip instead
1261 of compress. Also, --use-compress-program lets you specify any
1262 compress program. --compress-block is renamed --block-compress and
1263 now requires one of the three compression options to be specified.
1265 * Several error messages are cleaned up.
1267 * Directory owners are now set properly when running as root.
1269 * Provide DUMP_REMIND_SCRIPT in backup-specs as a possible option
1272 * Behave better with broken rmt servers.
1274 * Dump scripts no longer use --atime-preserve; this causes a nasty probem.
1276 * Several Makefile cleanups.
1278 Version 1.11.1 - Michael Bushnell, 1992-09.
1282 Version 1.11 - Michael Bushnell, 1992-09.
1283 Version 1.10.16 - 1992-07.
1284 Version 1.10.15 - 1992-06.
1285 Version 1.10.14 - 1992-05.
1286 Version 1.10.13 - 1992-01.
1290 * Now uses GNU standard configure, generated by Autoconf.
1292 * Long options now use '--'; use of '+' is deprecated and support
1293 for it will eventually be removed.
1295 * New option --null causes filenames read by -T to be
1296 null-terminated, and causes -C to be ignored.
1298 * New option --remove-files deletes files (but not directories)
1299 after they are added to the archive.
1301 * New option --ignore-failed-read prevents read-errors from affecting
1304 * New option --checkpoint prints occasional messages as the tape
1305 is being read or written.
1307 * New option --show-omitted-dirs prints the names of directories
1308 omitted from the archive.
1310 * Some tape drives which use a non-standard method of indicating
1311 end-of-tape now work correctly with multi-tape archives.
1313 * --volno-file: Read the volume number used in prompting the user
1314 (but not in recording volume ID's on the archive) from a file.
1316 * When using --multi-volume, you can now give multiple -f arguments;
1317 the various tape drives will get used in sequence and then wrap
1318 around to the beginning.
1320 * Remote archive names no longer have to be in /dev: any file with a
1321 ':' is interpreted as remote. If new option --force-local is given,
1322 then even archive files with a ':' are considered local.
1324 * New option --atime-preserve restores (if possible) atimes to
1325 their original values after dumping the file.
1327 * No longer does tar confusingly dump "." when you don't tell it
1330 * When extracting directories, tar now correctly restores their
1331 modification and access times.
1333 * Longnames support is redone differently--long name info directly
1334 precedes the long-named file or link in the archive, so you no
1335 longer have to wait for the extract to hit the end of the tape for
1338 Version 1.10 - Michael Bushnell, 1991-07.
1340 * Filename to -G is optional. -C works right. Names +newer and
1341 +newer-mtime work right.
1343 * -g is now +incremental, -G is now +listed-incremental.
1345 * Sparse files now work correctly.
1347 * +volume is now called +label.
1349 * +exclude now takes a filename argument, and +exclude-from does
1350 what +exclude used to do.
1352 * Exit status is now correct.
1354 * +totals keeps track of total I/O and prints it when tar exits.
1356 * When using +label with +extract, the label is now a regexp.
1358 * New option +tape-length (-L) does multi-volume handling like BSD
1359 dump: you tell tar how big the tape is and it will prompt at that
1360 point instead of waiting for a write error.
1362 * New backup scripts level-0 and level-1 which might be useful
1363 to people. They use a file "backup-specs" for information, and
1364 shouldn't need local modification. These are what we use to do
1365 all our backups at the FSF.
1367 Version 1.09 - Jay Fenlason, 1990-10.
1368 Version 1.08 - Jay Fenlason, 1990-01.
1369 Versions 1.07 back to 1.00 by Jay Fenlason.
1371 * See ChangeLog for more details.
1375 Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2003,
1376 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
1378 This file is part of GNU tar.
1380 GNU tar is free software; you can redistribute it and/or modify
1381 it under the terms of the GNU General Public License as published by
1382 the Free Software Foundation; either version 3, or (at your option)
1385 GNU tar is distributed in the hope that it will be useful,
1386 but WITHOUT ANY WARRANTY; without even the implied warranty of
1387 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1388 GNU General Public License for more details.
1390 You should have received a copy of the GNU General Public License
1391 along with tar; see the file COPYING. If not, write to
1392 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
1393 Boston, MA 02110-1301, USA.
1397 paragraph-separate: "[
\f]*$"
1398 eval: (add-hook 'write-file-hooks 'time-stamp)
1399 time-stamp-start: "changes. "
1400 time-stamp-format: "%:y-%02m-%02d"
1401 time-stamp-end: "\n"