title: How to list Processes started by multiprocessing Pool?
body: <p>While attempting to store <code>multiprocessing</code>'s <strong>process</strong> instance in <code>multiprocessing</code> list-variable 'poolList` I am getting a following exception:</p>
  
  <p><code>SimpleQueue objects should only be shared between processes through inheritance</code></p>
  
  <p>The reason why I would like to store the PROCESS instances in a variable is to be able to terminate all or just some of them later (if for example a PROCESS freezes). If storing a PROCESS in variable is not an option I would like to know how to get or to list all the PROCESSES started by <code>mutliprocessing</code> POOL. That would be very similar to what <code>.current_process()</code> method does. Except <code>.current_process</code> gets only a single process while I need all the processes started or all the processes currently running.</p>
  
  <p>Two questions:</p>
  
  <ol>
  <li><p>Is it even possible to store an instance of the <strong>Process</strong> (as a result of <code>mp.current_process()</code></p></li>
  <li><p>Currently I am only able to get a single process from inside of the function that the process is running (from inside of <code>myFunct()</code> using <code>.current_process()</code> method). </p></li>
  </ol>
  
  <p>Instead I would like to to list all the processes currently running by <code>multiprocessing</code>. How to achieve it?</p>
  
  <hr>
  
  <pre><code>import multiprocessing as mp
  
  poolList=mp.Manager().list()
  
  def myFunct(arg):
      print 'myFunct(): current process:', mp.current_process()
  
      try: poolList.append(mp.current_process())
      except Exception, e: print e
  
      for i in range(110):
          for n in range(500000):
              pass
          poolDict[arg]=i
      print 'myFunct(): completed', arg, poolDict
  
  from multiprocessing import Pool
  pool = Pool(processes=2)
  myArgsList=['arg1','arg2','arg3']
  
  pool=Pool(processes=2)
  pool.map_async(myFunct, myArgsList)
  pool.close()
  pool.join()
  </code></pre>