OK, except here's where I'm unclear. This command sorta does what I want: 
open (STDERR, '>', './log.txt')
   or die "could not open STDERR: $!\n";
It captures STDERR from child processes without any calls to system or backticks or whatever having to be called in a special way. The problem is that it only redirects to a file. Isn't there some way to redirect it to a subroutine or file handle instead?

In reply to Re^2: Capturing STDERR (this is not a FAQ) by mikosullivan
in thread Capturing STDERR (this is not a FAQ) by mikosullivan

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