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POProblem with exiting a daemonized process
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copied!<p>I am writing a daemon program that spawns several other children processes. After I run the <code>stop</code> script, the main process keeps running when it's intended to quit, this really confused me.</p> <pre><code>import daemon, signal from multiprocessing import Process, cpu_count, JoinableQueue from http import httpserv from worker import work class Manager: """ This manager starts the http server processes and worker processes, creates the input/output queues that keep the processes work together nicely. """ def __init__(self): self.NUMBER_OF_PROCESSES = cpu_count() def start(self): self.i_queue = JoinableQueue() self.o_queue = JoinableQueue() # Create worker processes self.workers = [Process(target=work, args=(self.i_queue, self.o_queue)) for i in range(self.NUMBER_OF_PROCESSES)] for w in self.workers: w.daemon = True w.start() # Create the http server process self.http = Process(target=httpserv, args=(self.i_queue, self.o_queue)) self.http.daemon = True self.http.start() # Keep the current process from returning self.running = True while self.running: time.sleep(1) def stop(self): print "quiting ..." # Stop accepting new requests from users os.kill(self.http.pid, signal.SIGINT) # Waiting for all requests in output queue to be delivered self.o_queue.join() # Put sentinel None to input queue to signal worker processes # to terminate self.i_queue.put(None) for w in self.workers: w.join() self.i_queue.join() # Let main process return self.running = False import daemon manager = Manager() context = daemon.DaemonContext() context.signal_map = { signal.SIGHUP: lambda signum, frame: manager.stop(), } context.open() manager.start() </code></pre> <p>The <code>stop</code> script is just a one-liner <code>os.kill(pid, signal.SIGHUP)</code>, but after that the children processes (worker processes and http server process) end nicely, but the main process just stays there, I don't know what keeps it from returning.</p>

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