Keep in mind this "quirk" is shell dependent.tingo, I'm not familiar with that use of one character in a bracket, and I can't find a web page search term that is working for me. (Nor skimming through some regex sites). Would you mind explaining why that [c]ups doesn't show the grep PID?
Thanks.
And as soon as I posted that I found the answer, that it prevents grep from matching itself. Going to add a thanks though, as I hadn't known about that one, and it is useful, in my opinion.
bash
and sh
will be fine. You might not get what you expect using csh/tcsh. Try it!