How to make function run by multiprocessing communicate

Question

While True loop is iterating I would like to emit a signal to update a waiting for it Child.process with a data such as an integer, dictionary or a string. In PyQt it could be done using PyQt.Signal object. Qt signal object can be set to be a string, dict or a list. The using signal.emit method it would be possible to "emit" a variable that could be "captured" by another object. How to make the function process to interact with a child and/or a parent without using PyQt signal object?

import time, multiprocessing

def process():
    num = int()
    while True:
        print '...sleeping %s' % num
        time.sleep(1)
        num += 1
        if num > 10:
            break
    return time.time() 


class Child(object):
    def __init__(self):
        super(Child, self).__init__()

    def process(self):
        proc = multiprocessing.Process(target=process)
        proc.start()

class Parent(object):
    def __init__(self):
        super(Parent, self).__init__()
        child = Child()
        time_completed = child.process()
        print 'time_completed: %s' % time_completed



obj = Parent()

Answer 1

Use multiprocessing.Queue object to make the process function communicate with the child and then with the parent object:

import time, multiprocessing

def process(queue):
    num = int()
    while True:
        queue.put('...sleeping %s' % num)
        time.sleep(1)
        num += 1
        if num > 5:
            break
    queue.put('...time completed %s' % time.time() ) 
    time.sleep(0.1)

class Child(object):
    def __init__(self):
        super(Child, self).__init__()
        self.queue = multiprocessing.Queue()
        self.proc = multiprocessing.Process(target=process, args=(self.queue,))

    def process(self):
        self.proc.start()

class Parent(object):
    def __init__(self):
        super(Parent, self).__init__()
        children = [Child() for i in range(3)]

        for child in children:
            child.process()

        for child in children:
            if child.proc.is_alive():
                if not child.queue.empty():
                    print child.queue.get()

obj = Parent()