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From: Devin Jeanpierre <jeanpierreda@gmail.com>
Date: Wed, 30 Nov 2011 17:41:33 -0500
Subject: Re: Need some IPC pointers
To: Andrew Berg <bahamutzero8825@gmail.com>
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> Sounds interesting, but I'm not familiar with threading (not that I
> wouldn't be willing to learn).
> Is it even possible to pipe into a running process, though?

You create the pipe to the process when you start it. e.g.

    subprocess.Popen(['ls', 'foo'], stdout=subprocess.PIPE,
stdin=subprocess.PIPE)

Irmen de Jong mentions the multiprocessing module, that might be a
better approach. I don't use it for production purposes because it has
bad properties when processes are killed abruptly (it can't tell
necessarily the difference between a truncated message and a normal
message). It doesn't feel safe, you know? (Of course, neither do
threads!)

Devin

On Wed, Nov 30, 2011 at 5:19 PM, Andrew Berg <bahamutzero8825@gmail.com> wrote:
> On 11/30/2011 3:32 PM, Devin Jeanpierre wrote:
>> You could also use threads and pipes. (I'm not actually
>> sure how threads+pipes works, but I'm told that it's a viable
>> approach).
> Sounds interesting, but I'm not familiar with threading (not that I
> wouldn't be willing to learn).
> Is it even possible to pipe into a running process, though?
>
>> For what it's worth, I wrote something potentially similar using Twisted
>> and AMP. AMP is an Asynchronous Messaging Protocol: this basically
>> means that clients and servers can send messages to each other at any
>> time in any order. Twisted makes sure that the right response gets
>> associated with the right message. This can be very convenient -- you
>> might request something from another process, and then to compute its
>> answer it might ask for some additional information from you, and then
>> you give it that information, and it sends back the final result.
>>
>> All the communication is done over TCP, usually using Twisted. So this
>> does involve bringing in a fairly large dependency.
> Sounds like overkill, but I'll take a look.
>
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