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Strange behavior of dict from Manager() in python's multiprocessing module

import multiprocessing as mp

def f(d):
  d['f'] = {}
  d['f']['msg'] = 'I am here'

manager = mp.Manager()
d = manager.dict()

p = mp.Process(target=f, args=(d,))

p.start()
p.join()

print d

d = {}
f(d)

print d


Output:

{'f': {}}
{'f': {'msg': 'I am here'}}



Whaa???? BUGREPORT!

Update: Some one has suffered before me.

Comments

  1. I just stumbled upon the same problem even in Python 2.7.1.

    ReplyDelete
  2. This is a known bug. I'm hitting it, though, since I'm constrained into using python 2.6 due to sysadmin trouble. http://bugs.python.org/issue6766

    Documented it here: http://justanyone.blogspot.com/2014/08/real-live-python-bug.html

    ReplyDelete

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