Arvados

Much like the -c in xen create guestname -c.

Adding this to arv job create should be fairly straightforward: instead of exiting, run arv job log --uuid {foo} (or whatever #3980 looks like).

Adding this to arv pipeline run --submit should be just as easy: after submitting, either exec() or just switch to arv pipeline run --log-only mode.

Adding this to arv pipeline run --run-pipeline-here is a bit trickier but it comes with a prize. Since the a-r-p-i process itself needs to keep running and monitoring the jobs anyway, it should listen to a websocket instead of polling. This part of the story is a lower priority, though (it's not the most common use case) so it should be set aside until the above features are implemented and merged.

arv pipeline run --run-jobs-here doesn't need this at all, of course.