Re: [dev] [sbase] Adding tar

From: Markus Wichmann <nullplan_AT_gmx.net>
Date: Sun, 7 Jul 2013 09:24:03 +0200

On Sat, Jul 06, 2013 at 10:53:01PM -0500, Galos, David wrote:
> > I also see it a lot in scripts, along with using full options instead
> > of short--perhaps to be more verbose? So, for compatibility, perhaps it
> > is best to allow both.
> If you mean GNU --long-options, then never in a million years :) If
> you mean both dashed and non, that is likely what I will do.
>
> Based on the very high incidence of use of non-dashed options, their
> inclusion is justifiable. In order to nicely support this, I think
> that the best option will be to attempt ARGBEGIN parsing, and as long
> as no flags are present, to fall back on simple non-dashed parsing.
>

You also could roll your own option parser. Which in this case is called
for, I think.

> > tar xzf filename.tar.gz -C ~/scratch/
> Crap.
> The -C flag seems like a good idea, but why'd you have to go
> and mix dashed and non like that?
>

One way I also find myself using quite often:

tar xfC filename.tar.gz directory
tar xCf directory filename.tar.gz

> > I usually use:
> >
> > gunzip < file.tar.gz | tar xf -
> Why can't everyone be more like you?
>

Convenience. ;-)

> I see that a lot of people rely on tar's integration with gzip,bzip2,xz,etc.
> Although convenient, it sucks, because that exact functionality can
> be so beautifully achieved with pipelines. Using a shell script to wrap
> tar with compression is trivial, but also defeats the whole point of
> complicating tar's option parsing for compatibility reasons.
>

You are right, of course. I have also seen problems with this approach
when it comes to parallelizing the decompression step (with the pipe
approach you can swap gzip for a parallel version of gzip, with the gtar
compression autodetection you cannot short of hacks like symlinking you
parallel gzip to gzip and putting it first in PATH or so).

> For now, tar will not do compression. If sbase gains programs to do
> compression, and the code is nicely librarized, I will consider thinking
> about considering adding letting tar do that.
>

Wait, libz and libbz2 and xzlib are not suckless enough?

>
> David Galos

Ciao,
Markus
Received on Sun Jul 07 2013 - 09:24:03 CEST