[Pkg-xfce-devel] Bug#762731: Bug#762731: lightdm: issues strange error message when requested to start but is non-default dm

[Yann Dirson]

On Wed, Sep 24, 2014 at 09:47:47PM +0200, Yves-Alexis Perez wrote:
> On mer., 2014-09-24 at 21:44 +0200, Yann Dirson wrote:
> > On Wed, Sep 24, 2014 at 09:24:59PM +0200, Yves-Alexis Perez wrote:
> > > On mer., 2014-09-24 at 21:17 +0200, Yann Dirson wrote:
> > > > kdm is the default dm here, and I just switched from systemd.  When
> > > > hunting various dm issues, I found that asking lightdm to start
> > > > results in the following unexpected error (it does start as expected
> > > > when set to be the default, however).  It should surely check the
> > > > default dm settings, like eg. xdm does, and does not even attempt to
> > > > start.
> > > 
> > > 
> > > Well, that's exactly what it's doing…
> > 
> > I'm not sure if you're saying that it does check the dm settings.  If
> > it's the case, then it looks like it causes the service start to error
> > out, causing systemd to retry to launch it, whereas it is a perfectly
> > legal situation for a dm to be disabled.  In that case, it is a change
> > from what we've been used to, and I'm not sure to see the advantages
> > of doing so.
> 
> Well, the same thing happens with sysvrc, the init.d script checks for
> the default display manager and errors out if it's not the selected one.

AFAICT, it really looks like it just does "exit 0", as do other DMs.


> > I tried to lookup any policy information about display managers, but
> > could not find any.  That makes me even more curious about how the
> > collaboration among maintainers of dm packages is organized.
> 
> See #733220

You mean, bugreports are the only collaboration ?

I would have thought that eg. the debconf stuff that has to be shared
(duplicated ?) in the various DM packages, could come from a central
package (a debhelper tool ?), around which some sort of DM policy
would live ?