I have a python script (unix-like, based on RHEL), called MyScript, that has two functions, called A and B. I'd like them to run in different, independent processes (detach B and A):
- Start script MyScript
- Execute function A
- Spawn a new process, passing data from function A to B
- While function B runs, continue with function A
- When function A completes, exit MyScript even if B is still running
I thought I should use multiprocessing to create a daemon process, but the documentation suggests that's not the right usecase. So, I decided to spawn a child process and child^2 process (the child's child), and then force the child to terminate. While this workaround appears to work, it seems really ugly.
Can you help me make it more pythonic? Does the subprocess module have a method that will operate on a function? Sample code below.
import multiprocessing
import time
import sys
import os
def parent_child():
p = multiprocessing.current_process()
print 'Starting parent child:', p.name, p.pid
sys.stdout.flush()
cc = multiprocessing.Process(name='childchild', target=child_child)
cc.daemon = False
cc.start()
print 'Exiting parent child:', p.name, p.pid
sys.stdout.flush()
def child_child():
p = multiprocessing.current_process()
print 'Starting child child:', p.name, p.pid
sys.stdout.flush()
time.sleep(30)
print 'Exiting child child:', p.name, p.pid
sys.stdout.flush()
def main():
print 'starting main', os.getpid()
d = multiprocessing.Process(name='parentchild', target=parent_child)
d.daemon = False
d.start()
time.sleep(5)
d.terminate()
print 'exiting main', os.getpid()
main()