Sharing a Result Queue among Several Processes Using multiprocessing.Manager

In multiprocessing, sharing a queue between parent and child processes is essential for communication and result retrieval. However, using apply_async to start asynchronous worker processes presents challenges in sharing queues.

To overcome the "Queue objects should only be shared between processes through inheritance" error, we can utilize multiprocessing.Manager. This manager class enables the creation and management of shared resources, including queues.

By enclosing our queue creation within the multiprocessing.Manager() context, we can make it accessible to all workers. This is how to modify the code:

if __name__ == '__main__':
    pool = multiprocessing.Pool(processes=3)
    m = multiprocessing.Manager()
    q = m.Queue()
    workers = pool.apply_async(worker, (33, q))

Now, each worker can interact with the shared q object and report results back to the base process. This approach allows for efficient and reliable result communication while maintaining the asynchronous nature of apply_async.