Bug#207431: post-update hook

[Adam Heath <doogie@debian.org>]

On Tue, 26 Aug 2003, Joey Hess wrote:

> Probably the best way to fix tasksel's bug #114721 (which our users
> stumble over again and again), as well as to remove a common FAQ would
> be for apt to get a post-update hook. Then dpkg or something else could
> drop a file into apt.conf.d to apt-cache dumpavail > /var/lib/dpkg/available

Note, it doesn't dump straight to dpkg's available file.  It uses an
intermediate file, and then tells dpkg to update /var/lib/dpkg/available with
that.

> I expect we might find other uses for such a hook as well. I'd never
> have expected DPkg::Pre-Install-Pkgs to be used by something like
> apt-listchanges when I helped add that hook to apt. Of course the dpkg
> available file may eventually go away, if dpkg 2.0 is ever finished, but
> we will have it for sarge, and this hook could be implemented before
> sarge is released.

dpkg itself will no longer be concerned with the list of available package
versions.  It'll only be concerned with the status of installed packages.

dselect, however, will need this information.  How apt will update that is
still unknown.