pipe question

["Fox, Kevin M" <KMFox mail bhi-erc com>]

I am writing a program that needs to spawn off a program, wait for it to
finish, and then continue executing while still refreshing itself.
I was thinking:

popen the program,
have a timeout function that checks to see if the program has closed,
continue when the program is done.

One problem.
I need a function similar to pclose in that it checks to see if the pipe is
closed, but does not wait for the program to close if the pipe is not
closed.

Thanks,
Kevin