[plug] RPM requires/provides question

[Derek Fountain]

I tried the following on the SuSE list, but got no response. Perhaps some RPM 
expert on here can help...?

In a desperate attempt to squeeze a little more diskspace for my choked server 
I wrote a script which examines all the packages on the box to see which ones 
aren't required by any others. I figured these "top leaves" can be removed if 
I know I'm not using them.

The script basically does a "rpm -q --provides" for a package, then for each 
provided capability, it does a "rpm -q --whatrequires". The packages which 
provides capabilities which aren't required by anything else are the ones I 
want.

During this process I came across tcsh, which I don't use. It doesn't provide 
much:

> rpm -q --provides tcsh
tcsh

and nothing uses that:

> rpm -q --whatrequires tcsh
no package requires tcsh

Ha! 2MB to be saved here! But:

# rpm --erase tcsh
error: removing these packages would break dependencies:
        /bin/csh is needed by transfig-3.2.3d-219
        /bin/csh is needed by samba-2.2.5-124

Oh. A check confirms:

> rpm -q --whatprovides /bin/csh
tcsh-6.12.00-40

Now I'm confused. The "--provides" operation on tcsh doesn't say it provides 
"/bin/csh", but the "--whatprovides" operation on the file says it does.

Why the inconsistency? I'm no expert on RPM. What have I misunderstood?

-- 
> eatapple
core dump