Exit (C-Q) sometimes hangs on "Reaping DSP process..."

[bgribble]

Not sure when this happens; seems to be associated with processors that have had error conditions? The instance that prompted this ticket was a patch with just one object, [plugin~ "zita-reverb"], which I had mistyped the name of the plugin a couple of times before successfully making the processor.

[bgribble]

I think the commit above gets the root cause of this: in some circumstances, there was a blocking call to process.stdout.readline() that never returned if the process on the other end died or quit at a bad time. This should (I would think) result in an IOError that would terminate the loop, but at least sometimes I could see that it was getting stuck there.

Closing this issue, will reopen if I see it again.