Author jjdmon
Recipients jjdmon, paul.moore, steve.dower, tim.golden, zach.ware
Date 2018-03-16.18:10:25
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <>
The following simple example code creates a started SyncManager and passes it as an argument to a subprocess started with multiprocessing.Process().  It works on Linux and Mac OS but fails on Windows.

import multiprocessing as mp

def subProcFn(m1):
if __name__ == "__main__":

    __spec__ = None
    m1 = mp.Manager()
    p1 = mp.Process(target=subProcFn, args=(m1,))

This is the traceback in Spyder:

runfile('D:/', wdir='D:')
Traceback (most recent call last):

  File "<ipython-input-1-534b9087bae9>", line 1, in <module>
    runfile('D:/', wdir='D:')

  File "...\anaconda3\lib\site-packages\spyder\utils\site\", line 705, in runfile
    execfile(filename, namespace)

  File "...\anaconda3\lib\site-packages\spyder\utils\site\", line 102, in execfile
    exec(compile(, filename, 'exec'), namespace)

  File "D:/", line 22, in <module>

  File "...\anaconda3\lib\multiprocessing\", line 105, in start
    self._popen = self._Popen(self)

  File "...\anaconda3\lib\multiprocessing\", line 223, in _Popen
    return _default_context.get_context().Process._Popen(process_obj)

  File "...\anaconda3\lib\multiprocessing\", line 322, in _Popen
    return Popen(process_obj)

  File "...\anaconda3\lib\multiprocessing\", line 65, in __init__
    reduction.dump(process_obj, to_child)

  File "...\anaconda3\lib\multiprocessing\", line 60, in dump
    ForkingPickler(file, protocol).dump(obj)

TypeError: can't pickle weakref objects
Date User Action Args
2018-03-16 18:10:26jjdmonsetrecipients: + jjdmon, paul.moore, tim.golden, zach.ware, steve.dower
2018-03-16 18:10:26jjdmonsetmessageid: <>
2018-03-16 18:10:25jjdmonlinkissue33088 messages
2018-03-16 18:10:25jjdmoncreate