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Date: Sat, 16 Jul 2011 09:34:40 +1000
Subject: Re: Python threading/multiprocessing issue.
From: Chris Angelico <rosuav@gmail.com>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:9582

2011/7/16 Lee Harr <missive@hotmail.com>:
> I am not a multiprocessing expert, but I think the problem you
> are having is that Process is running your code in a separate
> process, so there is no way you could see those object changes
> in your main line code.
>
> In other words, Process is not an exact replacement for Thread.
>

That's correct; inter-process communication is the realm of sockets
(network or Unix), pipes, signals, etc - but inter-thread
communication is a matter of making sure you don't tread on each
other's toes. In CPython, the latter is guaranteed by the GIL; the
specific advantage of multiprocessing over threading is that each
process has a separate GIL, and that's because all variables are
separate.

ChrisA