tar( bzip2 parts of manpage )
Danny Pansters
danny at ricin.com
Sun Mar 9 23:20:36 UTC 2008
On Sunday 09 March 2008 23:52:59 Markus Klaschka wrote:
> Hi,
> I never used built-in bzip functionality of tar, but I like bzip2 more
> than gzip, so I just searched and found following:
> -j (c mode only) Compress the resulting archive with bzip2(1).
> In extract or list modes, this option is ignored. Note that, unlike
> other tar implementations, this implementation recognizes
> bzip2 compression automatically when reading archives.
> and
> -y (c mode only) Compress the resulting archive with bzip2(1).
> In extract or list modes, this option is ignored. Note that, unlike
> other tar implementations, this implementation recognizes
> bzip2 compression automatically when reading archives.
>
> what's going on there?
>
> I tested the -j option, works good. I created a file.tar.bz2 and like
> the manpage describes, tar -cvf is enough to unpack the tarball,
you mean tar xvf
> Is that a FreeBSD feature, how is it on other platforms?
> Is bzip2 used, or is that build in as a tar?
bsdtar != gtar
In bsdtar -j (-y) indeed uses bzip2 to compress rather than gzip and upon
unpacking it handles both tgz and tbz transparantly that's why you don't need
to specify -j there (different from gtar IIRC). I think -j and -y are mainly
there to be compatible with gtar but I'm not sure. Note that both bsdtar and
bzip2 are in base and have been for a while so it seems like a logical
feature for bsdtar. Knowing whether its a gzip or bzip2 compressed is easy to
see from magic numbers.
Cheers,
Dan
>
> Cheers
>
> -
> Markus Klaschka
> MKDev - Markus Klaschka Development
> http://www.mkdev.eu
>
> Spain: 0034 - 63 747 23 07
> UK:
> 0044 - 750 910 2718
> Mail: mk at mkdev.eu <mailto:mk at mkdev.eu>
> Skype: mark-use
> IRC: mark-use @ irc.freenode.net : #freebsd, ##security, #freebsd-src,
> #bsdforen.de, #bsdgroup.de
More information about the freebsd-questions
mailing list