Python: How to determine subprocess children have all finished running

Question

I am trying to detect when an installation program finishes executing from within a Python script. Specifically, the application is the Oracle 10gR2 Database. Currently I am usi

Answer 1

Ok, here is a trick that will work only under Unix. It is similar to one of the answers to this question: Ensuring subprocesses are dead on exiting Python program. The idea is to create a new process group. You can then wait for all processes in the group to terminate.

pid = os.fork()
if pid == 0:
    os.setpgrp()
    oracle_subprocess = subprocess.Popen(OUI_DATABASE_10GR2_SUBPROCESS)
    oracle_subprocess.wait()
    os._exit(0)
else:
    os.waitpid(-pid)

I have not tested this. It creates an extra subprocess to be the leader of the process group, but avoiding that is (I think) quite a bit more complicated.

I found this web page to be helpful as well. http://code.activestate.com/recipes/278731-creating-a-daemon-the-python-way/