I have put fixes into CVS to get Csound 5 compiling again with PortAudio. I 
would appreciate it if people with better Linux audio systems than I would 
test real-time audio with the new code.

I have removed the PortAudio blocking code from Linux. Linux now uses the 
same PortAudio callback based code as the other platforms (pa_blocking.c). 

I really dislike the callback model; it caused real problems earlier
with Mac, and it adds another layer of copying as far as I can see.
==John ffitch