I have a 2-CD "Official Debian GNU/Linux 2.1" set, LinuxMall edition; or just plain 'slink'. I'd like to experiment with the 'potato' distribution (which has an improved SVGA X server needed with my video hardware), and then configure apt to get the needed spuds off the web, (running under dselect in hopes that this is the easiest way), but also have it so that it gets any duplicate files from the CD set.
If this isn't so clear, here's a generic example: given a dselect-ed request for 'foo.deb', what's wanted is to have that file looked up in whatever package database apt uses, and then compare the version number of 'foo.deb' on the CD- ROM with that of the online potato 'foo.deb'. If the slink CDs have this same version, it'd be better to get the particular package from the CDs, but if the online potato distrib has a newer version of 'foo.deb', then the object is to have apt fetch that online copy instead. One minor difficulty is that, so far as I can tell, dselect only allows one to add Debian distribution locations to its apt method. I can use dselect to add 'ftp://ftp.debian.org' to apt's list of places to look for .deb files, but later on if I want apt to quit looking there, there's apparently no menu option to make dselect forget a particular apt address. Currently my apt list from dselect has gotten large and unwieldy, so it's no longer clear which location has priority. So, if dselect doesn't allow one to fine tune an apt location list, the question is: which config file for apt should be edited? Another question might be whether this usage of apt is reasonable or even possible to begin with. Any pointers to relevant docs, HOWTO's, hints, and so forth would help too and be much appreciated as well.