How to get qubes-guid to inherit DISPLAY from qvm-start/run?

[Ilpo Järvinen]

Hi,

The multiple dom0 X/shm.id/DISPLAY functionality I wrote for R3.2 which
was included into some pre-R4.0 version and I've successfully used
off-tree in R3.2 (it was, obviously, considered too invasive to go into
stable) seems to not work fully in R4.0 because some of the later changes
prevent qubes-guid from inheriting the DISPLAY from the caller of the
qvm-start / qvm-run. If I kill the qubes-guid that is created by default
and manually run qvm-gui-start in the dom0 of the DISPLAY is correctly
inherited and I successfully get the VM's GUI displayed by the correct
X/DISPLAY.

I guess it got broken by the inclusion of the admin API. I'd like to
restore this functionality as I find it very useful but I don't fully
understand how the qubes-guid is actually started in R4.0 (in the
qvm-start/qvm-run case) to get the correct DISPLAY passed to qubes-guid.

--
i.

[Marek Marczykowski-Górecki]

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There is qvm-start-gui --all --watch process responsible for starting
gui daemon whenever new VM is started. $DISPLAY is inherited from this
process.
If you want different VMs on different dom0 X servers, it shouldn't be
that hard to have separate qvm-start-gui processes to handle different
set of VMs. Right now --watch option makes it start qubes-guid for each
newly started VM (regardless of --all, or an explicit domains list). But
it would be ok to extend the tool to take into account domains list also
with --watch option. Or even add an option to filter based on tags, not
a plain list. This way you can start separate qvm-start-gui for each X
server session, for appropriate set of VMs.

- --
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
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