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I don't understand why Pipes are said unsafe when there are multiple senders and receivers. How the following code can be turned into code using Queues if this is the case ? Queues don't throw EOFError when closed, so my processes can't stop. Should I send endlessly 'Poison' messages to tell them to stop (this way, i'm sure all my processes receive at least one poison) ? I would like to keep the pipe p1 open until I decide otherwise (here it's when I have sent the 10 messages). from multiprocessing import Pipe, Process from random import randint, random from time import sleep def job(name, p_in, p_out): print(name + ' starting') nb_msg = 0 try: while True: x = p_in.recv() print(name + ' receives ' + x) nb_msg = nb_msg + 1 p_out.send(x) sleep(random()) except EOFError: pass print(name + ' ending ... ' + str(nb_msg) + ' message(s)') if __name__ == '__main__': p1_in, p1_out = Pipe() p2_in, p2_out = Pipe() proc = [] for i in range(3): p = Process(target=job, args=(str(i), p1_out, p2_in)) p.start() proc.append(p) for x in range(10): p1_in.send(chr(97+x)) p1_in.close() for p in proc: p.join() p1_out.close() p2_in.close() try: while True: print(p2_out.recv()) except EOFError: pass p2_out.close()

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