Bug#531611: gnome-session: postinst fails when calling update-alternatives

[Raphael Hertzog]

On Wed, 03 Jun 2009, Josselin Mouette wrote:
> Le mardi 02 juin 2009 à 20:25 +0200, Wolf Wiegand a écrit :
> > after the upgrade from 2.22.3-3 to 2.26.1-6, the postinst fails with the
> > following error:
> > 
> > Setting up gnome-session (2.26.1-6) ...
> > Installing new version of config file /etc/gnome/defaults.list ...
> > update-alternatives: error: alternative x-session-manager.1.gz can't be slave of
> >  x-session-manager: it is a master alternative.
> > dpkg: error processing gnome-session (--configure):
> >  subprocess installed post-installation script returned error exit status 2

Can you provide us the content of
/var/lib/dpkg/alternatives/x-session-manager.1.gz and the output of
stat /var/lib/dpkg/alternatives/x-session-manager.1.gz ?

Does the timestamps correlate with a particular package installation (see
/var/log/dpkg.log*) ?

> I guess this is an issue with another provider of this alternative
> (maybe icewm-session). I’ve seen recent changes on the
> update-alternatives side, so could a dpkg maintainer give an explanation
> about what changed and how it could trigger this issue?

The change is that update-alternatives forbids mistakes but as people
(users and packagers) did mistakes in the past we have some cruft
left-over that are in contradiction with the actual usage of alternatives.


For users, the simple work-around is "rm 
/var/lib/dpkg/alternatives/x-session-manager.1.gz" but please provide the
infos requested above before-hand.

See 530633 for another case, I will centralize some cleanup in dpkg
installation scripts for cases where we can't be certain that a particular
package was at fault (or where too-many packages would have to implement
the work-around).

Cheers,
-- 
Raphaël Hertzog

Contribuez à Debian et gagnez un cahier de l'admin Debian Lenny :
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