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Subject: Re: Pipe buffers' limit of 16 * 4K
From: Miquel van Smoorenburg <miquels@cistron.nl>
To: Fausto Richetti Blanco <fausto.blanco@gmail.com>
Cc: linux-kernel@vger.kernel.org, riel@redhat.com, jengelh@medozas.de
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Date: Thu, 29 May 2008 15:19:24 +0200
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On Thu, 2008-05-29 at 10:00 -0300, Fausto Richetti Blanco wrote:
> Yes, I need an unspecified amount (it is the data content of a HTTP POST).
> 
> The tee system call appeared in the 2.6.17 (I'm using 2.6.9). That's
> because I did my implementation using a buffer and copying it using
> write. Unfortunately, both solutions suffer from the kernel buffer
> limitation.
> 
> As I said, there's a lot of other solutions to my specific problem.
> I'll problably move my solution inside the lib =/ But I decided to
> write to this list to ask for dynamically adjustable sizes for the
> pipes' buffers. Is there any good reason for this not to be pushed to
> the kernel head ?

Why not use a socketpair() instead of a pipe(). You can adjust the size
with setsockopt SO_SNDBUF/SO_RCVBUF (see man socket(7))

Mike.