multiprocessing.Pool() problem in windows

[SirLalala]

BPO	7122
Nosy	@amauryfa
Files	prueba.py: test code

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = <Date 2009-10-14.12:04:11.132>
created_at = <Date 2009-10-14.11:42:48.201>
labels = ['invalid', 'library']
title = 'multiprocessing.Pool() problem in windows'
updated_at = <Date 2009-10-14.12:04:11.122>
user = 'https://bugs.python.org/SirLalala'

bugs.python.org fields:

activity = <Date 2009-10-14.12:04:11.122>
actor = 'amaury.forgeotdarc'
assignee = 'none'
closed = True
closed_date = <Date 2009-10-14.12:04:11.132>
closer = 'amaury.forgeotdarc'
components = ['Library (Lib)']
creation = <Date 2009-10-14.11:42:48.201>
creator = 'SirLalala'
dependencies = []
files = ['15123']
hgrepos = []
issue_num = 7122
keywords = []
message_count = 2.0
messages = ['93975', '93977']
nosy_count = 2.0
nosy_names = ['amaury.forgeotdarc', 'SirLalala']
pr_nums = []
priority = 'normal'
resolution = 'not a bug'
stage = None
status = 'closed'
superseder = None
type = None
url = 'https://bugs.python.org/issue7122'
versions = ['Python 2.6']

[SirLalala]

Maybe I didn't understand how multiprocessing works but when running the
test code below I get 200+ processes in Windows and it never finishes.
It works fine on Linux.

[amauryfa]

This difference between Unix and Windows is documented there:
http://docs.python.org/library/multiprocessing.html#windows
Please carefully read the paragraph named "Safe importing of main module".

You will certainly need to add a condition like
if __name__ == '__main__':
so that subprocesses (which start a new Python interpreter from the
start) don't start another Pool themselves.