[kwlug-disc] Purging already removed Debian packages.

[Chris Frey]

On Fri, May 14, 2010 at 02:16:55PM -0400, Chris Irwin wrote:
> A nice feature of aptitude is that it will perform an autoremove of
> unneccessary packages. So if you install MyApp, and it requires
> libMyApp, aptitude will also remove the library (as long as nothing
> else needs it). apt-get would simply leave the library around to
> clutter up your system, unless you manually sought them out.

My version of apt-get has an 'autoremove' command too.

I think these things work in such a way, that the tools record which
apps that you actively select, and which ones that just got included
as a dependency.  It's the dependencies that get removed automatically.
Which means that if you did an "apt-get install library", then that
library won't get removed.

That's my understanding anyway... it might be wrong, as I haven't tested
recently.  I do remember that during my last upgrade to Lenny, the old
apt-get did not have this feature, and aptitude "remembered" these facts
in its own way.  And since I wasn't using aptitude, it didn't know what apps
I had manually selected.

- Chris