Re: location management vs. session management

[Glynn Foster <glynn foster sun com>]

Hey Havoc,

> I'm curious about the master plan for session management and location
> management, and their combination.

You mean there is a master plan for session management?? Crikey, no
one told me :) Well actually I've been thinking a lot about this too 
and the more I think about it, the more complicated this gets.

> As I understand it, the current UI/plan for session management is that
> on login, you can name your session, say "big screen session" or "work
> session" or whatever.

Yes, the way it works is probably wrong in that we really should be 
sticking to some spec and using ID's, but I think the idea of named
sessions is much more user friendly, if a little hacky. I'd quite 
like to do saving per-display as well, but I'm not sure if it's 
neccessary, since you can load a specific session using the 
--choose-session option. Still, it might be a useful feature to
have gnome-session pick up on an env var and save a session named 
'hostname:display' or something. I'm open to ideas :)

> Then the settings I change during the session will be saved
> per-session. Applications can also choose to save some settings as
> global (applying to all sessions). For example, the panel setup is
> certainly per-session, but my http proxy may not be.  (It's hard to
> know how this should work, exactly. For GConf we had hashed out a plan
> that would allow people to configure it on a per-key level if they
> were willing to drop down to the command line, and have reasonable
> defaults otherwise.)

The way I'm currently hacking the mutli-session panel is by picking up
on an env var that gnome-session sets and loading the appropriate
panel session from ~/.gnome/panel.d/ and not having the option at
the moment to have settings that apply to all panel sessions. 

Again, I should probably be using ID's.

> Anyhow, on login I can also choose an existing session to use as
> appropriate, so I'd choose my "big screen session" when I have a big
> screen.
> 
> We could also easily implement session copying, so I could base one
> session on another. At least I'm pretty sure we could do this (the SM
> would pass the previous session ID to clients on startup, but then
> when they registered, give them a new session ID, perhaps?). This
> would happen at session creation time; I create a new session named
> "foo" and it lets me choose another session to base it on.

Hrm, I'm not entirely sure of this....and maybe it's because I don't
understand this well enough [or even SM stuff well enough :)]...but
at the moment, you could just log on to 'big screen session', use the 
crapplet, create a new session called 'big screen session cloned' and
then save your session...or at least, that should work.

> So how does this relate to location management? Say I have several
> locations; are sessions "inside" a location? Or are locations "inside"
> a session?

AFAIK, the location management stuff is only in Ximian Setup Tools...but
I could be wrong about this? My idea is that the location management
stuff should really only save X/network etc.. configuration and let 
gnome-session [multi-session] worry about the desktop. Of course that
means that applications have to become multi-session aware.

> How do I choose a location? If gdm already lets you choose a session,
> does it make sense to have the user choose both a session and a
> location in gdm? Or is there some other UI for choosing a location?

Hrm, I have no clue about this. It seems strange because you have to
log into a session, run the location manager and then presumably it
restarts the machine or something? I haven't used it so I don't know.

> To put that concretely, if the panel has session-specific config
> files, do location settings go in those files or in global files?

See previous comment about letting gnome-session be in control of
the desktop and location manager be in control of the other X/network
etc. stuff.
 
> Sessions work with non-GNOME apps. For example, I am trying to get it
> into Mozilla, and it works with Qt apps. Can locations ever work with
> non-GNOME apps? Or are they intended to work with apps at all - is it
> just desktop settings? What if I want to have location-specific stuff
> in my word processor or web browser?
> 
> I'm concerned that it's confusing to have both "locations" and
> "sessions," and maybe we need to think this through a bit more.

I can see it working okay if we go with the suggestion above. Maybe
the location manager would mere set the name of the session to load
by default? But again, I would prefer it not to and leave that to
gdm and gnome-session.

> 
> I'm not really familiar with the details of either one, but I'd like
> to be. Comments welcome.

Well I'm not truely familiar with gnome-session either ;P


				See ya,
					Glynn ;)