how to *completely* remove a package from the cmd line?

[Tyler J. Wagner]

On Tuesday 10 Aug 2010 13:46:27 Robert P. J. Day wrote:
>   sure, i get all that, but am i just being confused in not seeing how
> that applies to, say, the authbind package above?  it's been removed
> (not purged), and "dpkg -L" shows no files in that package.  but
> there's clearly *something* still related to that package on my
> system ...

The package left nothing behind. However, the package manager has retained 
some of the package data in /var/lib/dpkg. See "status" and "info/" in that 
directory.

I don't know why your command-line purge didn't work originally, but "dpkg -P 
authbind" will definitely complete the job.

I installed authbind, then removed it, and it has status "rc", but no files. 
Snipped for brevity:

root at baal:~# apt-get install authbind
root at baal:~# dpkg -l authbind
ii  authbind            1.2.0build3         Allows non-root programs to bind() 
to low ports
root at baal:~# apt-get remove authbind
root at baal:~# dpkg -l authbind
rc  authbind            1.2.0build3         Allows non-root programs to bind() 
to low ports
root at baal:~# dpkg -L authbind
Package `authbind' does not contain any files (!)
root at baal:~# dpkg -P authbind
root at baal:~# dpkg -L authbind
Package `authbind' is not installed.
root at baal:~# dpkg -l authbind
un  authbind            <none>              (no description available)

I tested this with the "hello" package, and it shows as uninstalled after a 
normal install, with no configs. So I dug deeper. The difference between the two 
packages is the postrm script:

root at baal:/var/lib/dpkg/info# cat authbind.postrm
#!/bin/sh
# $Id: postrm,v 1.1 1998/08/30 02:35:22 ian Exp $
set -e
if test "$1" = purge
then
        rm -rf /etc/authbind
fi

It appears that authbind deletes /etc/authbind on purging, which may have files 
you've manually created there. On normal removal it leaves this directory 
alone. I suspect that dpkg leaves a package as mode "rc" when it has a postrm 
script.

Your original problem was "what clutter did authbind leave on my system?" The 
answer is "none, except whatever configs you created in /etc/authbind. Purge 
the package and it'll remove it for you.

Regards,
Tyler


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