[xmonad] Going Gnomeless (and Unityless on Oneiric)

[Jacek Generowicz]

Brandon Allbery wrote:

> On Mon, Jan 16, 2012 at 18:08, Jacek Generowicz <jacek.generowicz at cern.ch>wrote:

> > sudo /usr/bin/X :1 -auth /var/run/lightdm/root/:1 -nolisten tcp vt8 -novtswitch
> 
> That's going to start an X server running nothing and with no way for
> anything else to connect to it; not very useful.

That would explain the black screens then :-) But how come something
equivalent seems to be running on :0 and doing something useful?

> Display managers are usually designed to support multiple sessions; that
> is, instead of running a separate display manager for each display, you
> have a single display manager which manages multiple displays.

So I should be able to get the already-running instance of LightDM to
open a new session for me? Presumably, that's exactly what 'switch
user' does. Only I don't want to switch user, I want to run another
session for the same one.

> It also appears that LightDM documentation is nonexistent.
> https://answers.launchpad.net/lightdm/+question/179211 is about how to
> manage multiple displays; while it gives a recipe, it also notes that the
> only way to work this stuff out currently is to read the source code.  :/

From the above URL:

   Overall, any unknown keyword or unexpected configuration in the
   conffile is silently ignored

Hmmm. That's encouraging. Sigh.

By 'multiple seats' does he mean that LightDM will run a login screen
on :0 :1 :2 etc.? So I could have my working session on :0 and keep
starting new ones to experiment on :1? But will the display mananager
have to be restarted to pick up changes in desktop files?

> > Any hints where to find documentation on these files?
> 
> http://standards.freedesktop.org/desktop-entry-spec/desktop-entry-spec-latest.html
>
> The session files are the same format, and are supposed to be / work the
> same whether used from gdm, kdm, lightdm, etc.

Another coin drops, as stray bits of information that have (weakly)
penetrated my head over the last week, collect into a slightly more
meaningful whole.

Much appreciated.