add a special Provides: to all login manager packages

[Colin Walters]

On Wed, Feb 18, 2009 at 5:37 PM, Colin Walters <walters at verbum.org> wrote:
>  Changing the login system has a *huge*
> impact on how everything works and could easily result in confusing
> problems higher up the stack.

Just to give a concrete example, how GDM uses PAM is highly
nontrivial, involving separate processes because of PAM's
ill-specified nature among other things.  GDM also interacts with
various complex cases like smartcards that in turn involve other
system daemons.  There is quite a bit happening inside GDM/PAM even on
a default desktop that may not be obvious, such as how gnome-keyring
saves your password to unlock the keyring.  How gnome-keyring works
depends on various bits of infrastructure including dbus (this is a
tricky issue).  NetworkManager in turn depends on gnome-keyring.

So yes, swapping out the login manager could quite easily result in
not being able to log in to your WPA network. It turns out an
operating system is a very complex thing, and we have plenty enough
bugs without people trying to replace parts of it without coordinating
with consumers higher up the stack.

Anyways...back to those bugs.