[PATCH xserver] check for elevated privileges rather than just euid=0

[Jamey Sharp]

On 10/6/11, Michal Suchanek <hramrach at centrum.cz> wrote:
> I would like to check this out but how do I tell this actually works?
>
> Xephyr and Xvfb already run as non-root, Xorg needs device access to
> run which will likely fail as non-root.

The motivation for Antoine's patch is the xf86-video-dummy driver, and
the same problems come up with xf86-video-nested. You could try either
of those. The thread that Antoine cited in the commit message has more
information on setting up an appropriate xorg.conf.

Hopefully, someday, device access won't require root either, and this
is a step in the right direction for that too. KMS drivers could
probably run unprivileged with little work...

Jamey