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Date: Mon, 20 Aug 2007 22:58:26 -0400
From: "Xin Zhao" <uszhaoxin@gmail.com>
To: linux-kernel <linux-kernel@vger.kernel.org>,
       linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: How Linux /proc filesystem convert a fd to the actual pathname?
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Hi,

In the Linux proc filesystem,  /proc/[pid]/fd is a link to the
actually the actual pathname of the opened file.

I am curious how Linux convert an fd to the pathname?  Does it
recursively walk back from current dentry to the root?

Can someone point me to the right place in the kernel where this
functionality is implemented?

Many thanks in advance!

-x