SIGSTOP and SIGCONT for VJs

My friend Dan had asked me a while ago if it was possible to run two VJ applications, but have one ‘paused’ while you work in the first and then ‘pause’ it and unpause the second app (say you want to play with VDMX and then Modul8, or.. more realistically Brush and then Vade). Now by pause we mean stopped and using no scheduler/CPU time. I knew this was possible, but the KILL manpage wasnt any help, untill I realized that it pointed me in the right direction:

“man 2 sigaction”

Duh. RTFM and all.

So, kill -SIGSTOP (pid) and kill -SIGCONT (pid) will pause and unpause the app associated with the pid you give it. Fun. Now you can run Brush with Modul8 using no CPU in the background. You can verify this by running ‘top’ and checking the CPU usage. Aint UNIX grand? Im sure this is old news to the unix sysadmins out there…

Now to write a simple Applescript wrapper…

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