Re: [xmonad] Going Gnomeless (and Unityless on Oneiric)

Brandon Allbery wrote:

On Mon, Jan 16, 2012 at 18:08, Jacek Generowicz 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-lates...

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.