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Date: Thu, 2 Jul 2009 18:04:02 +0800
Message-ID: <412e6f7f0907020304u166b6d17id1bcf5d334b45c53@mail.gmail.com>
Subject: Re: PROPOSAL: extend pipe() to support NULL argument.
From: Changli Gao <xiaosuo@gmail.com>
To: Amerigo Wang <xiyou.wangcong@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Thu, Jul 2, 2009 at 5:46 PM, Amerigo Wang<xiyou.wangcong@gmail.com> wrote:
>>Are you familiar with splice() and tee()? They both use pipes as kernel buffers.
>
> You are not answering the question, obviously.
When you use pipes as kernel buffer handlers, two fd isn't necessary.
Using one will save half of fd resources. Is it obviously?

>
> And you snipped too much, how can you return that fd? Using the return value?
one RW file descriptor is returned. I have answered this in the first post.

> Ah! This will probably break the user-space program...
>
I don't think so. As a skillful programmer, who will trasfter pipe() a
NULL pointer? In any way, it is break sth, but not very seriously, and
won't affact any right and robust program.


-- 
Regards，
Changli Gao(xiaosuo@gmail.com)