Re: How to make a meta package unremovable?

[David Kalnischkies <kalnischkies@gmail.com>]

On Thu, Jun 9, 2011 at 22:54, Erik Schanze (Debian) <schanzi_@gmx.de> wrote:
> Does anybody have an additionally idea how to solve this, to prevent the
> removal of one package without hanging on user input and prevent
> automatic inclusion in PBuilder installation?

With my APT hat on i can tell you that APT (and friends) currently have no
option to forbid the removal of packages without other side-effects.

You can set a package on hold, so that it will not be removed, but it will
also not be considered for an upgrade.
(You can use this in you pbuilder - set the non-installed package on hold
 and it will not be considered for installation)

For essentials you have already listed the problems with it.

What could be done is tweaking resolver scoring points, but honestly:
that is black-magic even for me -- and as you can only change this for
priorities it has side-effects for other packages with this priority and
these would be still allowed to remove your package…
(i said this only for completeness, i would not recommend to even try it)


So, back to square one: Interesting feature.
I might give it a try for next or next-next abi break
(pkgDepCache::IsDeleteOk() can be used for this, but if it's implemented
 similar to APT::NeverAutoRemove we will need aggressive caching or some
 operations will get "horrible" slow - e.g. aptitude would "love" it)


Best regards

David Kalnischkies