There is the IPC::Open2 (and the Open3) module in core to make this more painless, but if you're going to write the output of the process to stdout or another file you could use a simple piped open like this: 
open PIPE, "|program >$file";
print PIPE "testing.  output will go to $file, since perl will pass th
+e command line though the shell\n";

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integral, resident of freenode's #perl

In reply to Re: Confusion with two-way pipes by integral
in thread Confusion with two-way pipes by Anonymous Monk

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