Sharing object (class instance) using multiprocessing Managers

Question

I need to share an object and its methods between several processes in python. I am trying to use `managers` (in module `multiprocessing`) but it crashes. Here is a silly example of producer-consumer where the shared object between the two processes is just a list of numbers with four methods. ``` from multiprocessing import Process, Condition, Lock from multiprocessing.managers import BaseManager import time, os lock = Lock() waitC = Condition(lock) waitP = Condition(lock) class numeri(object): def __init__(self): self.nl = [] def getLen(self): return len(self.nl) def stampa(self): print self.nl def appendi(self, x): self.nl.append(x) def svuota(self): for i in range(len(self.nl)): del self.nl[0] class numManager(BaseManager): pass numManager.register('numeri', numeri, exposed = ['getLen', 'appendi', 'svuota', 'stampa']) def consume(waitC, waitP, listaNumeri): lock.acquire() if (listaNumeri.getLen() == 0): waitC.wait() listaNumeri.stampa() listaNumeri.svuota() waitP.notify() lock.rel…

Accepted Answer

You must join your processes to prevent main process exiting before child processes continue their execution. So add joins to your code:

```
 consumer.join()
 producer.join()
```

after you called `start()` methods of your processes.

Sharing object (class instance) using multiprocessing Managers

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