You should almost always post `see perldoc perldiag` instead of cutting and pasting. You're reminding the person that they should be looking in the documentation for their answers (and here is where your current answer is).
I mentioned where the documentation actually is, which I think is a sufficient reminder that the OP should look there in the future. I think a quick ^C & ^P of the part that interests them is an added bonus - since I already went to the effort of looking it up, why shouldn't I save someone else the trouble?