I wrote:
> Even if I could simply pipe the output to a command-line recorder that
> would be enormously useful. Currently, realtime output goes outside the
> computer whether I want it to or not.

I should clarify this: I think I can get realtime MIDI input while
Csound writes a soundfile (haven't tried yet), but there'd be no way to
hear what I was playing. OK-- can anyone think of a way to record an
output file AND hear realtime output at the same time?? Is that a tough
nut to crack? It's worth cracking. Help!

I think there are a couple of Linux-specific tools that may help me,
I'll go look into it and report back here.