Re: first draft "aptitude howto"

[Daniel Burrows <Daniel_Burrows@brown.edu>]

On Tue, Apr 04, 2000 at 12:52:50AM -0500, Steve Greenland was heard to say:
> On 03-Apr-00, 21:31 (CDT), Daniel Burrows <Daniel_Burrows@brown.edu> wrote: 
> >   (this isn't technically true..aptitude extends apt's cache with its own
> >    information to get some features not yet supported by apt..I don't think
> >    this matters to the newbies, but there are a few cases where it might be
> >    confusing (aptitude will try to detect changes in dselect package
> >    selections, but I can't make dselect listen to aptitude))
> 
> Ack. If I understand this correctly, you're saying that once I use
> aptitude, dselect will no longer correctly represent the state of the
> system. You may even be implying that 'dpkg --get-selections' won't
> be correct. Either of those would be make me never-ever-ever install
> aptitude. (More accurately, rush to de-install it...)

  I was expecting at least one person to say this :)

  I agree that it's a hack.  I'd prefer to have it implemented at the apt level,
or at the dpkg level.

  However, here's what it means practically: if you mark a package as
to-be-installed, to-be-removed, or to-be-held in aptitude, dselect won't know
about it.  The only major concern here is to-be-held.  I could maybe add some
hacks to aptitude to mirror Hold states in dselect using dpkg --set-selections,
but this could get hairy.  Tracking changes made in dselect is hairy enough
already.

> But please consider the downside of making the use of aptitude a one-way
> trip.

  I did at the time that I decided to do things this way, and I actually tried
to do things using the dselect database.  But there's already some stuff that
isn't representable without changes to the dselect status information (allowing
packages to be marked as both New and Install, for example), and more is likely
to come in the future (target versions for example, so you can downgrade)  I
really don't have time to rewrite dpkg.
  If it makes you happy, I can add an option to turn off some of the useful
features of aptitude and make it only use the dselect cache.  I also remember
encountering difficulties with calling dpkg --set-selections, surprisingly
(if I remembered what they were, I'd tell you :) -- it might have been a
selection)  I'll take a look.  Or if you have time, check the CVS out and
modify generic/apt.cc..

  Daniel

-- 
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