[Lzip-bug] Tarlz 0.8 released

[Antonio Diaz Diaz]

I am pleased to announce the release of tarlz 0.8.

Tarlz is a small and simple implementation of the tar archiver. By 
default tarlz creates, lists and extracts archives in a simplified posix 
pax format compressed with lzip on a per file basis. Each tar member is 
compressed in its own lzip member, as well as the end-of-file blocks. 
This method is fully backward compatible with standard tar tools like 
GNU tar, which treat the resulting multimember tar.lz archive like any 
other tar.lz archive. Tarlz can append files to the end of such 
compressed archives.

Tarlz can create tar archives with four levels of compression 
granularity; per file, per directory, appendable solid, and solid.

Of course, compressing each file (or each directory) individually is 
less efficient than compressing the whole tar archive, but it has the 
following advantages:

   * The resulting multimember tar.lz archive can be decompressed in
     parallel with plzip, multiplying the decompression speed.

   * New members can be appended to the archive (by removing the EOF
     member) just like to an uncompressed tar archive.

   * It is a safe posix-style backup format. In case of corruption,
     tarlz can extract all the undamaged members from the tar.lz
     archive, skipping over the damaged members, just like the standard
     (uncompressed) tar. Moreover, the option '--keep-damaged' can be
     used to recover as much data as possible from each damaged member,
     and lziprecover can be used to recover some of the damaged members.

   * A multimember tar.lz archive is usually smaller than the
     corresponding solidly compressed tar.gz archive, except when
     individually compressing files smaller than about 32 KiB.

Note that the posix pax format has a serious flaw. The metadata stored 
in pax extended records are not protected by any kind of check sequence. 
Because of this, tarlz protects the extended records with a CRC in a way 
compatible with standard tar tools.

The homepage is at http://www.nongnu.org/lzip/tarlz.html

An online manual for tarlz can be found at 
http://www.nongnu.org/lzip/manual/tarlz_manual.html

The sources can be downloaded from
http://download.savannah.gnu.org/releases/lzip/tarlz/tarlz-0.8.tar.lz

The sha256sum is:
413507c2bf624c82266496c5207d2627b40ea3507faba07763d8994a2a72df4f 
tarlz-0.8.tar.lz


Changes in version 0.8:

  * The new option '--anonymous', equivalent to '--owner=root 
--group=root', has been added.

  * On extraction and listing, tarlz now removes leading './' strings 
also from member names given in the command line. 'tarlz -xf foo ./bar' 
now extracts member 'bar' from archive 'foo'. (Reported by Viktor 
Sergiienko in the bug-tar mailing list).

  * Tarlz now writes extended headers with all fields zeroed except 
size, chksum, typeflag, magic and version. This prevents old tar 
programs from extracting the extended records as a file in the wrong 
place (with a truncated filename). Tarlz now also sets to zero those 
fields of the ustar header overridden by extended records.

  * The chapter 'Amendments to pax format', explaining the reasons for 
the differences with the pax format, has been added to the manual.


Please send bug reports and suggestions to address@hidden


Regards,
Antonio Diaz, tarlz author and maintainer.
Europe, wake up! There are political prisoners on hunger strike in Spain.
--
If you are distributing software in xz format, please consider using 
lzip instead. See http://www.nongnu.org/lzip/lzip_benchmark.html#xz1 and 
http://www.nongnu.org/lzip/xz_inadequate.html