g_spawn_sync and child PID

[Allin Cottrell <cottrell wfu edu>]

I'm reasonably familiar with the usage of both g_spawn_sync and 
g_spawn_async, but recently I've found myself wanting to do domething that 
seems to fall between the two and I can't quite work out how to do it.

Here's the task: I want to spawn an mpiexec process from my GTK app and, 
assuming all goes well, wait for the result (in itself that's a case of 
g_spawn_sync). But I also want to know the PID of mpiexec, so that I can 
give the user the option of killing that process "prematurely" if it seems 
to be going wrong. (This is based on the observation that an MPI_Bcast 
call, for example, can hang at 100% CPU if one or more of the processes 
launched by mpiexec bombs out at just the wrong moment.)

Any suggestions on how to achieve this using g_spawn* (or judgements on 
whether it's even possible) would be gratefully received.

--
Allin Cottrell
Department of Economics
Wake Forest University, NC