scanning parent/child process IDs using os.fork

fork.py

import os

parent_pid = os.getpid()
print "[parent] starts PID: %d" % (parent_pid, )

forked_pid = os.fork()
if forked_pid == 0:
    print "[child] child process can't use os.fork() PID, since it's %d" % (forked_pid, )
    print "[child] but it can reevaluate os.getpid() to get it's own PID: %d" % (os.getpid(), )
else:
    print "[parent] parent process have created child with PID: %d" % (forked_pid, )