systemd user session integration

[Auke Kok]

All,

I'd like to start a quick project to properly integrate Xfce4 with 
systemd. There are several parts needed here, but it's not too hard to 
do so.

Some concepts, before we start:

[1] systemd starts everything. No cheating and forking off helper processes
[2] socket activation is better than dbus activation is better than 
launching
[3] processes involved should signal when they are "complete" or "ready".

What I've done so far with systemd --user:

- start xfce4-session through a service file
- pray it all works

What I'd like to see/create:

- a comprehensive non-xfce4 session based way of starting most xfce4 
components through separate systemd unit files without xfce4-session 
starting them for us.
- socket activation for services that are socket-based (?)
- dbus activation for services that are dbus based (xfconfd)
- sd-notify() usage for each of the daemons to signal when they are 
"ready-for-service"
- xfce4-session can stay but should not start things like Thunar 
--daemon, xfdesktop etc. under a systemd --user session
- logind integration in systemd.

The end result should use pkg-config "systemd" and be conditional on the 
return value - rather trivial of course (man 7 daemon).

Anyone interested in working with me in figuring out the bits needed to 
improve this part?


Auke