should ldm warn about multiple logins?

[Jonathan Carter]

Hi Gavin

Gavin McCullagh wrote:
> it seems one or two of our users are logging in from multiple thin clients.
> Any time I've done this, even temporarily, I immediately see bug-buddy pop
> up as some evolution calendar component segfaults.  I'm sure also that
> firefox, gnome, etc. are not happy for multiple sessions to run on one
> profile.  Sometimes the earlier session is a dead one lying around,
> sometimes the user has forgotten they had another login and sometimes they
> just don't realise this is a bad idea. 

Yes! LDM *should* check whether a user is logged in already, but it is 
not implemented yet.

> I wonder would it be possible to (perhaps optionally) have ldm
> 
> 1. prompt for username/password
> 2. ssh in and check for existing sessions on the server

I think you could have an even simpler implementation. There has been 
lots of talk about implementing a messenging system between the server 
and the client, so that the client could ask about user information 
(amongst many other things), and find out whether a user is logged in 
(and where they are logged in, and for how long), so that this 
information can be relayed back to the client.

> 3. if another session exists give a warning and offer to either
>    a. kill the existing session
>    b. abort this session
>    c. carry on regardless

Ooh, that sounds quite nice!

> 4. ssh in and start session as normal.
> 
> I can put this in launchpad if it's realistic.  I'd just like a few
> opinions on whether this is sane or silly first.

LDM is currently going through a re-write. The original LDM is written 
in Python, and as far as I know the new implementation will be written 
in C (Oli, please correct me if I'm wrong). Now that I think about it, 
I'm a bit surprised that this wasn't slotted in for a session at the 
Developer's summit. Perhaps there should be a launchpad/wiki page for 
the LDM rewrite, and all of this could be integrated into that.

-Jonathan