http://www.perlmonks.org?node_id=1218532

ovedpo15 has asked for the wisdom of the Perl Monks concerning the following question:

Hey guys.
Consider a function (lets call it A) which returns 1 if a process finished running, otherwise 0.
I would like to write another function which should wait until the process will finish running.
What's the best why to do it?

I thought of using the while loop and the wait(30); command.
Something like this:

until(A()) { sleep(30); }
I also can just call this subroutine until it will finish, although I don't think its smart because of all unnecessary junk.
What's the best way to do so?
I'm looking for the cleanest way to do it.