I assume you want to catch the STDERR of a program, then you can do this: 
open(HANDLE, "my_prg 2>&1 |") || die "error: $!\n";

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or 
$output = `my_prg 2>&1`;

[download]

In reply to RE: Getting STDERR to write to STDOUT? by autark
in thread Getting STDERR to write to STDOUT? by Pearte

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