This seems like it might be a bug...can anyone point me to somewhere in the docs where this is documented behavior?

Certainly. perldoc open (at least, my local pod) states:

   In the 2-arguments (and 1-argument) form opening
   '-' opens STDIN and opening '>-' opens STDOUT.

[download]

It specifically declines to mention 3-arg open.

--
edan

In reply to Re^2: Swiching between output to file and STDOUT by edan
in thread Switching between output to file and STDOUT by loris

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