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Date: Wed, 01 Aug 2012 10:19:19 +0200
From: Laszlo Nagy <gandalf@shopzeus.com>
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To: andrea crotti <andrea.crotti.0@gmail.com>
Subject: Re: Pass data to a subprocess
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Xref: csiph.com comp.lang.python:26339

>
> As I wrote "I found many nice things (Pipe, Manager and so on), but
> actually even
> this seems to work:" yes I did read the documentation.
Sorry, I did not want be offensive.
>
> I was just surprised that it worked better than I expected even
> without Pipes and Queues, but now I understand why..
>
> Anyway now I would like to be able to detach subprocesses to avoid the
> nasty code reloading that I was talking about in another thread, but
> things get more tricky, because I can't use queues and pipes to
> communicate with a running process that it's noit my child, correct?
>
Yes, I think that is correct. Instead of detaching a child process, you 
can create independent processes and use other frameworks for IPC. For 
example, Pyro.  It is not as effective as multiprocessing.Queue, but in 
return, you will have the option to run your service across multiple 
servers.

The most effective IPC is usually through shared memory. But there is no 
OS independent standard Python module that can communicate over shared 
memory. Except multiprocessing of course, but AFAIK it can only be used 
to communicate between fork()-ed processes.