Re: Problem with Archiving .tar

Mark Nichols wrote:

On 10/30/07, Derek Broughton <news@xxxxxxxxxxxxxx> wrote:

Chris Lemire wrote:

tar doesn't use compression. It just creates archives. If you want
compression, you should use bzip2 or gzip in combination with tar.

Why deliberately try to confuse users? Of course tar uses compression.

$ tar --help | egrep "\-[zj]"
--no-ignore-command-error treat non-zero exit codes of children
as
-i, --ignore-zeros ignore zeroed blocks in archive (means EOF)
-j, --bzip2 filter the archive through bzip2
-z, --gzip, --gunzip, --ungzip filter the archive through gzip

Oh - looks like tar uses compression...


Actually it looks like tar has the ability to filter its output _through_
bzip2 or gzip. Tar in an off itself doesn't do compression.

From the point of view of the user, tar accepts the option and performs the
operation. It's NOT like piping the output of tar into gzip, though you
can do that if you want. So yes, I stand by my statement that tar _does_
use compression, and saying anything else to a user who's having trouble
with tar and compression is needlessly confusing.
--
derek


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