Date: Thu, 5 Nov 2009 17:36:03 +0100
From: Max Kellermann <max@duempel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: linux-kernel@vger.kernel.org, mk@cm4all.com
Subject: Re: [PATCH] pipe: don't block after data has been written
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On 2009/11/05 17:27, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> Your patch breaks many programs, that dont use poll()/select()
> 
> char result[1000000];
> main()
> {
> 	computethings();
> 	write(1, buffer, 1000000);
> }

Your code does not check the return value of write().  This is a bug.

So how exactly does my patch break this program?

Let's read some more of the manual you cited: "If a write() requests
that more bytes be written than there is room for (for example, the
process' file size limit or the physical end of a medium), only as
many bytes as there is room for shall be written."
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