Take look at the poll() methods in the subprocess.py source file of your Python install.
It shows how to use the os.wait_pid(pid, os.WNOHANG) to check whether a process is still running or has terminated (and how, from the returned status value). Btw, on *nix you must call os.wait_pid(pid, ...) to avoid creating zombie processes. Using the subprocess module hides and handles all those details for you, both on *nix and Windows. /Jean Brouwers -- http://mail.python.org/mailman/listinfo/python-list