I agree, your example is correct, that's how fork works.

My demo above is what i'm doing. If I run that from the command line, it executes twice, yes. But if apache executes it, some_cmd is only executed once. I expect it has something to do with my close STDOUT line, which in a normal script apparently is a synonym for exit() (when run by apache). So, really, I don't understand why it ran some_cmd once, when it should have been either none or twice, I could rationally explain either of those outcomes