This would be a really, really weird case if it ever happens (i.e.,
you have usnics but the agent process failed somewhere in MPI_INIT
such that the agent never appears), but having an infinite loop
doesn't seem like a good idea.
(does not need to go to v1.8 because v1.8 still uses RML for
communication for the connectivity checker)
This commit was SVN r31932.