[systemd-devel] [HEADS-UP] If you are working on a multi-seat aware display manager

[Lennart Poettering]

On Thu, 21.06.12 14:06, Lennart Poettering (lennart at poettering.net) wrote:

> Heya,
> 
> just a quick heads up if you are hacking on a multi-seat aware display
> manager: with current git there is a new property CanGraphical on each
> seat, and you probably should update your display manager to care for
> this field, so that you properly handle seats which lack graphical
> support. The main reason we added this field is to fix a race: when the
> system comes up it might do so with a text console only, which is then
> later on turned into a graphical one as the KMS driver is loaded and
> video probed. We nowadays boot so fast that this might happen at a time
> where your display manager has already been started, so you need to
> watch CanGraphical so that you don't end up trying to start X11 on seat0
> at a time where the KMS driver is not around yet.
> 
> There is also a new variable CanTTY for the reverse, which is handy in
> some cases for USB graphics devices where the VT logic is not
> available. This also paves the way for CONFIG_VT less kernels, like the
> ones David Herrmann is working on.
> 
> I have updated the wiki to reflect this:
> 
> http://www.freedesktop.org/wiki/Software/systemd/writing-display-managers

The bug I filed about this against gdm, in case you are interested:

https://bugzilla.gnome.org/show_bug.cgi?id=678535

Lennart

-- 
Lennart Poettering - Red Hat, Inc.