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Date: Tue, 6 Dec 2005 04:09:30 -0800
From: kernel coder <lhrkernelcoder@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: zero copy
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hi,
i'm trying to track the code flow of sendfile system call.Mine
ethernet card doesn't have scatter gather and checksum calculation
features.So stack should be making a copy of data.

Please tell me where in sendfile code flow,check for scatter gather
and cecksum features is made so that stack can decide whether to copy
data from user space or not.

lhrkernelcoder