[Tutor] Linux help required

[Bruce Sass]

On Mon, 14 May 2001, Remco Gerlich wrote:

> On  0, alan.gauld@bt.com wrote:
> > > | that the zip file can't be opened by gunzip under Linux. I have
> >
> > Thanks to Deirdre for pointing out that gunzip only works on
> > single files, I hadn't realised that - I've only used in on
> > Unix up til now where tgz is the norm...
>
> It's exactly the same on Unix and Linux. .tgz even means tar/GNU zip.
>
> A .tgz is usually called .tar.gz. That is, you make an archive out of a
> bunch of files, the .tar, then you gzip that, and it's called .tar.gz,
> sometimes abbreviated .tgz for people using DOS or similar systems.
>
> That's two commands to make a compress archive, although GNU tar has an
> option to combine the two, so it's one command again.

I don't really want to muddy the waters, but this should be
mentioned...

"tar -cz" vs "tar | gzip"
I recall hearing about a problem between unix variants where the
result of the GNU tar's combined command could not be processed by
some non-GNU tar + gz commands.  So, two command versions were the
recommended way of making a portable tarball.

It is hearsay, and may be a historical footnote, but it has me doing:
"tar -cz" --> .tgz	and	"tar | gz" --> .tar.gz
just so's I have a clue if something strange happens with tarballs.


<...>
> Most distributions do have zip/unzip commands. Someone was talking about
> Debian, maybe it's those pedants whining about 'Free' again ;-)
>
> gzip is GNU zip, or as Free as it gets, anyway.

There is no freedom in Terms and Conditions.


> PS bzip2 is a lot better, of course. <grin, duck and run>

just look'n for trouble today, eh :)

.bz2 is nice for archiving, where space is most important; but sucks
for downloads 'cause it takes longer to un-compress the savings than
it does to download a not so compressed scheme -- very noticeable on a
slow system.


- Bruce