netbsd-help: Maintaining distfiles?

Subject: Maintaining distfiles?
To: None <netbsd-help@netbsd.org>
From: Richard Rauch <rauch@eecs.ukans.edu>
List: netbsd-help
Date: 12/21/2000 14:38:28

(I wasn't sure if this should go to netbsd-help, or tech-pkg; I opted for
the former...also, since I read these lists via the web-page, please
CC: replies to me.)
Is there something that I'm missing about maintaining distfiles? In
particular, I want to remove distfiles that are no longer referenced. 
(Most commonly, this happens when pkgsrc is updated and a new version of
the distfile is called for, of course.)
I can think of a few somewhat-clunky ways. Is there a clean way that I've
missed? The clunky ways are:
 * Delete all distfiles periodically. This might be acceptable if I had
 a faster Internet connection.
 * Just let them accumulate.
 * Do a ``touch time-stamp'', then ``make checksum'' on all packages and
 remove the unreferenced. The problem here is that it brings _all_
 pkgsrc distfiles onto my computer. In the past, this hasn't been too
 bad, since I already installed most of the big ones that I was aware
 of (EMACS, XEmacs, GNOME, KDE, the GIMP, ...). However, it looks like
 (in addition to many smaller packages, as pkgsrc has grown) we now have
 a new champion for space-hogging: Crafty. I don't intend on installing
 Crafty, and from the sound of it, at least one of its compressed data
 files is going to top 6GB. That's a lot of data to download and keep
 around just for the privilege of deleting old distfiles.
 * Throw hardware at the problem (get a faster link) and go back to
 the first solution. (^&
Is there a better way to do this? I've never snaked through the pkgsrc
Makefiles, since they didn't look too inviting; what kind of trouble would
I be letting myself in for if I tried to add some kind of ``make
prunedistfiles'', or some such?
Thanks in advance for any suggestions/help.
 "I probably don't know what I'm talking about." --rauch@eecs.ukans.edu