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Date: Thu, 02 Aug 2012 08:10:59 +0200
From: Laszlo Nagy <gandalf@shopzeus.com>
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To: python-list@python.org, andrea.crotti.0@gmail.com
Subject: Re: Pass data to a subprocess
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> I still don't get it.  shm_unlink() works the same way unlink() does.
> The resource itself doesn't cease to exist until all open file handles
> are closed. From the shm_unlink() man page on Linux:
>
>         The operation of shm_unlink() is analogous to unlink(2): it
>         removes a shared memory object name, and, once all processes
>         have unmapped the object, de-allocates and destroys the
>         contents of the associated memory region. After a successful
>         shm_unlink(), attempts to shm_open() an object with the same
>         name will fail (unless O_CREAT was specified, in which case a
>         new, distinct object is created).
>         
> Even if the parent calls shm_unlink(), the shared-memory resource will
> continue to exist (and be usable) until all processes that are holding
> open file handles unmap/close them.  So not only will detached
> children not crash, they'll still be able to use the shared memory
> objects to talk to each other.
>         
I stand corrected. It should still be examined, what kind shared memory 
is used under non-linux systems. System V on AIX? And what about 
Windows? So maybe the general answer is still no. But I guess that the 
OP wanted this to work on a specific system.

Dear Andrea Crotti! Please try to detach two child processes, exit from 
the main process, and communicate over a multiprocessing queue. It will 
possibly work. Sorry for my bad advice.