[GRASS5] session within a session

[Hamish]

> > I was just able to start a grass57 session from within another
> > grass57 session by mistake (different location). I had thought there
> > was a check to see if GRASS was already running?
> 
> The check has been removed; you are supposed to be able to run
> multiple sessions now.
> 
> Each session now has its own $GISRC and its own /tmp subdirectory for
> monitor sockets.


Ok, the problem remains though: you shouldn't be able to start one GRASS
session from within another GRASS session causing a confused state.

ie test for $GISBASE in current shell during startup, not for any
existing .gislock like files?

Running multiple sessions in parallel is ok, running multiple sessions
in serial is bad.


Hamish