Sorry, that's wrong. system waits for its child processes to complete. The big difference between it and backticks is that backticks will allow you pick up the output. Please read the top part of the relevant doc.

Looks like he just has a typo: Shouldn't the last line be: system("lp -d ep5_hpp01 $temp/*.ps");Presuming that $temp is a directory name. Else it'll glob to any .ps files in the current directory. Otherwise I can't think of why it would appear to be running the commands in parallel.

HTH