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Date: Tue, 28 May 2013 00:56:54 -0400
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Subject: Re: copyin+copyout in one step ?
From: Zaphod Beeblebrox <zbeeble@gmail.com>
To: Luigi Rizzo <rizzo@iet.unipi.it>
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On Mon, May 27, 2013 at 7:38 PM, Luigi Rizzo <rizzo@iet.unipi.it> wrote:

>
> say a process P1 wants to use the kernel to copy the content of a
> buffer SRC (in its user address space) to a buffer DST (in the
> address space of another process P2), and assume that P1 issues the
> request to the kernel when P2 has already told the kernel where the
> data should go:
>

Urm... Isn't the use of shared memory the more obvious way to transfer data
between processes?  Am I missing some nuance?