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gnu tar 源码包。 tar 软件是 Unix 系统下的一个打包软件

GNU tar NEWS - User visible changes. 2008-04-14
Please send GNU tar bug reports to <[e-mail]>


version 1.20 - Sergey Poznyakoff, 2008-04-14

* New option --auto-compress (-a)

With --create, selects compression algorithm basing on the suffix
of the archive file name.

* New option --lzma

Selects LZMA compression algorithm

* New option --hard-dereference

During archive creation, dereferences hard links and stores the files
they refer to, instead of creating usual hard link members (type '1').

* New option --checkpoint-action

This action allows to specify an action to be executed upon hitting a
checkpoint.  Recognized actions are: dot, echo (the default),
echo=string, ttyout=string, exec=cmdline, and sleep=value.  Any number
of `--checkpoint-action' options can be specified, the actions will be
executed in order of their appearance in the command line.  See
chapter 3.8 "Checkpoints" for a complete description.

* New options --no-check-device, --check-device.

The `--no-check-device' option disables comparing device numbers during
preparatory stage of an incremental dump.  This allows to avoid
creating full dumps if the device numbers change (e.g. when using an
LVM snapshot).

The `--check-device' option enables comparing device numbers.  This is
the default.  This option is provided to undo the effect of the previous
`--no-check-device' option, e.g. if it was set in TAR_OPTIONS
environment variable.

* The --transform option.

Any number of `--transform' options can be given in the command line.
The specified transformations will be applied in turn.

The argument to `--transform' option can be a list of replace
expressions, separated by a semicolon (as in `sed').

Filename transformations are applied to symbolic link targets
during both creation and extraction.  Tar 1.19 used them only
during extraction.

For a detailed description, see chapter 6.7 "Modifying File and Member
Names". 

* Info (end-of-volume) scripts

The value of the blocking factor is made available to info and
checkpoint scripts via environment variable TAR_BLOCKING_FACTOR.

* Incremental archives

Improved (sped up) extracting from incremental archives.

* Bugfixes.
** Fix bug introduced in version 1.19: tar refused to update non-existing
archives.


version 1.19 - Sergey Poznyakoff, 2007-10-10

* New option --exclude-vcs

Excludes directories and files, created by several widely used version
control systems, e.g. "CVS/", ".svn/", etc.

* --exclude-tag and --exclude-cache options

The following options now work with incremental archives as well:

  --exclude-caches       
  --exclude-caches-all   
  --exclude-tag
  --exclude-tag-all
  --exclude-tag-under

* Fix handling of renamed files in listed incremental archives.

Previous versions always stored absolute file names in rename
records, even if -P was not used. This is fixed: rename records
contain file names processed in accordance with the command line
settings.
  
* Fix --version output.

* Recognition of broken archives.

When supplied an archive smaller than 512 bytes in reading mode (-x,
-t), the previous version of tar silently ignored it, exiting with
code 0. It is fixed. Tar now issues the following diagnostic message:
'This does not look like a tar archive', and exits with code 2.

* Fix double-dot recognition in archive member names in case of duplicate '/.'.

* Fix file padding in case of truncation of the input file to zero size.


version 1.18 - Sergey Poznyakoff, 2007-06-29

* Licensed under the GPLv3

* Fixed several bugs in the testsuite


version 1.17 - Sergey Poznyakoff, 2007-06-08

* Fix archivation of sparse files in posix mode.  Previous versions padded
  sparse members with spurious zero blocks.

* Fix operation of --verify --listed-incremental.  Version 1.16.1 produced
  a full dump when both options were given.

* Fix --occurrence.  In previous versions it continued scanning the archive
  even though all requested members has already been extracted.

* Scope of --transform and --strip-components options.

In addition to affecting regular archive members, the --transform
option affects hard and soft link targets and the --strip-components
option affects hard link targets as well.

* End-of-volume script can send the new volume name to tar by writing
  it to the file descriptor stored in the environment variable `TAR_FD'.


version 1.16.1 - Sergey Poznyakoff, 2006-12-09

* New option --exclude-tag allows to specify "exclusion tag files", i.e.
  files whose presence in a directory means that the directory should not
  be archived.

* The --exclude-cache option excludes directories that contain the
  CACHEDIR.TAG file from being archived.  Previous versions excluded
  directory contents only, while the directories themselves were
  still added to the archive.

* Support for reading ustar type 'N' header logical records has been removed.
  This GNU extension was generated only by very old versions of GNU 'tar'.
  Unfortunately its implementation had security holes; see
  <http://archives.neohapsis.com/archives/fulldisclosure/2006-11/0344.html>.
  We don't expect that any tar archives in practical use have type 'N'
  records, but if you have one and you trust its contents, you can
  decode it with GNU tar 1.16 or earlier.

* Race conditions have been fixed that in some cases briefly allowed
  files extracted by 'tar -x --same-owner' (or plain 'tar -x', when
  running as root) to be accessed by users that they shouldn't have been.


version 1.16 - Sergey Poznyakoff, 2006-10-21

* After creating an archive, tar exits with code 1 if some files were
changed while being read.  Previous versions exited with code 2 (fatal
error), and only if some files were truncated while being archived.

* New option --mtime allows to set modification times for all archive
members during creation.

* Bug fixes
** Avoid running off file descriptors when using multiple -C options.
** tar --index-file=FILE --file=- sent the archive to FILE, and
the listing to stderr.


version 1.15.91 - Sergey Poznyakoff, 2006-06-16

* Incompatible changes

** Globbing

Previous versions of GNU tar assumed shell-style globbing when
extracting from or listing an archive.  For example:

  tar xf foo.tar '*.c'

would extract all files whose names end in '.c'.  This behavior
was not documented and was incompatible with traditional tar
implementations.  Therefore, starting from this version, GNU tar
no longer uses globbing by default.  For example, the above invocation
is now interpreted as a request to extract from the archive the file
named '*.c'.

To treat member names as globbing patterns, use --wildcards option.
If you wish tar to mimic the behavior of versions up to 1.15.90,
add --wildcards to the value of the environment variable TAR_OPTIONS.

The exact way in which tar interprets member names is controlled by the
following command line options:

     --wildcards              use wildcards
     --anchored               patterns match file name start
     --ignore-case            ignore case
     --wildcards-match-slash  wildcards match `/'

Each of these options has a '--no-' counterpart that disables its
effect (e.g. --no-wildcards).

These options affect both the interpretation of member names from
command line and that of the exclusion patterns (given with --exclude
and --exclude-from options). The defaults are:

 1. For member names: --no-wildcards --anchored
 2. For exclusion patterns: --wildcards --no-anchored --wildcards-match-slash

The options can appear multiple times in the command line, thereby
changing the way command line arguments are interpreted.  For example,
to use case-insensitive matching in exclude patterns and to revert to
case-sensitive matching for the rest of command line, one could write:

  tar xf foo.tar --ignore-case --exclude-from=FILE --no-ignore-case file.name

** Short option -l is now an alias of --check-links option, which complies
with UNIX98.  This ends the transition period started with version 1.14.

* New features

** New option --transform allows to transform file names before storing them
in the archive or member names before extracting.  The option takes a
sed replace expression as its argument.  For example,

  tar cf foo.tar --transform 's,^,prefix/,'

will add 'prefix/' to all file names stored in foo.tar.

** --strip-components option works when deleting and comparing.  In previous
versions it worked only with --extract.

** New option --show-transformed-names enables display of transformed file
or archive.   It generalizes --show-stored-names option, introduced in
1.15.90.  In particular, when creating an archive in verbose mode, it lists
member names as stored in the archive, i.e., with any eventual prefixes
removed and file name transformations applied.  The option is useful,
for example, while comparing `tar cv' and `tar tv' outputs.

** New incremental snapshot file format keeps information about file names
as well as that about directories.

** The --checkpoint option takes an optional argument specifying the number
of records between the two successive checkpoints.   Optional dot
starting the argument intructs tar to print dots instead of textual
checkpoints.

** The --totals option can be used with any tar operation (previous versions
understood it only with --create).  If an argument to this option is
given, it specifies the signal upon delivery of which the statistics
is to be printed.  Both forms of this option (with and without
argument) can be given to in a single invocation of tar.

* Bug fixes
** Detect attempts to update compressed archives.


version 1.15.90 - Sergey Poznyakoff, 2006-02-19

* New features

** Any number of -T (--files-from) options may be used in the command line.
The file specified with -T may include any valid `tar' options,
including another -T option.
Compatibility note: older versions of tar would only recognize -C
as an option name within the file list file.  Now any file whose name
starts with - is handled as an option.  To insert file names starting with
dash, use the --add-file option.

** List files containing null-separated file names are detected and processed
automatically.  It is no longer necessary to give the --null option.

** New option --no-unquote disables the unquoting of input file names.
This is useful for processing output from `find dir -print0'.
An orthogonal option --unquote is provided as well.

** New option --test-label tests the archive volume label.
If an argument is specified, the label is compared against its value.
Tar exits with code 0 if the two strings match, and with code 2 if
they do not.

If no argument is given, the --verbose option is implied.  In this case,
tar prints the label name if present and exits with code 0.

** New option --show-stored-names.  When creating an archive in verbose mode,
it lists member names as stored in the archive, i.e., with any eventual
prefixes removed.  The option is useful, for example, while comparing
`tar cv' and `tar tv' outputs.

** New option --to-command pipes the contents of archive members to the
specified command.

** New option --atime-preserve=system, which uses the O_NOATIME feature
of recent Linux kernels to avoid some problems when preserving file
access times.

** New option --delay-directory-restore delays restoring modification times
and permissions of extracted directories until the end of extraction.
This is necessary for restoring from archives with unusual member
ordering (in particular, those created with --no-recursion option).
This option is implied when restoring from incremental archives.

** New option --restrict prohibits use of some potentially harmful tar
options.  Currently it disables '!' escape in multi-volume name menu.

** New options --quoting-style and --quote-chars control the way tar
quotes member names on output. The --quoting-style takes an argument
specifying the quoting style to use (literal, shell, shell-always,
c, escape, locale, clocale). The argument to --quote-chars is a string
specifying characters to quote, even if the selected quoting style
would not quote them otherwise. The option --no-quote-chars is
provided to disable quoting certain characters.

** The end-of-volume script (introduced with --info-script option) can
get current archive name from the environment variable TAR_ARCHIVE and
the volume number from the variable TAR_VOLUME.  It can alter the
archive name by writing new name to the file descriptor 3.

** Better support for full-resolution time stamps.  Tar cannot restore
time stamps to full nanosecond resolution, though, until the kernel
guys get their act together and give us a system call to set file time
stamps to nanosecond resolution.

** The -v option now prints time stamps only to 1-minute resolution,
not full resolution, to avoid using up too many output columns.
Nanosecond resolution is now supported, but that would be too much.

* Bug fixes

** Allow non-option arguments to be interspersed with options.
** When extracting or listing archives in old GNU format, tar
used to read an extra block of data after a long name header
if length of the member name was divisible by block size (512).
Consequently, the file pointer was set off and the next member
was not processed correctly.
** Previous version created invalid archives when files shrink
during reading.