Nevermind...stupid yet subtle mistake...
I wasnt chomping the result from STDIN...
should have done this:
chomp($filename=<STDIN>);

this removes the newline character which kept getting inserted into $filename, giving $filename a value such as '/path/file\n', and thus passing the newline into my $cmd string, making $cmd look like this:

$cmd = "mycmd -args $filename >outfile"
...gives...
"mycmd -args /path/file\n >outfile"

So, everytime I passed $cmd to system(), it would execute the cmd and stop at the newline character embedded within $filename, thus skipping the ">outfile" redirection...

problem solved, but thanks to everyone for pointing out that this apparently should have worked.
Please add this to your vast collection of mental "gotchas" that can stump users...

In reply to Re^2: problem with system(), stdin, and stdout by romero619
in thread problem with system(), stdin, and stdout by romero619

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