groups.google.com returned this on a search for can't spawn nowait 

I actually just figured this out about an hour ago.  Add 

waitpid $pid, 0;

to your script when you are done with each individual call 
to IO::Pipe.  That frees up the resource that is hanging 
onto a dead process.open2 can only handle a limited number 
of processes (128 or 64), so you have to unleash the process 
by waiting for it to close itself (waitpid).
HTH
slayven

In reply to Re: 'can't spawn nowait' by slayven
in thread 'can't spawn nowait' by compualley

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