From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andries Brouwer <aebr@win.tue.nl>
Subject: Re: [Fwd: [Bug 136] New: FSID returned from statvfs always 0]
Date: Tue, 10 Dec 2002 00:04:18 +0100
Sender: linux-fsdevel-owner@vger.kernel.org
Message-ID: <20021209230418.GA9444@win.tue.nl>
References: <3DED43F7.AD396584@digeo.com> <20021204032511.GA7646@win.tue.nl> <at34lg$gck$1@cesium.transmeta.com>
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Cc: linux-fsdevel@vger.kernel.org
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To: "H. Peter Anvin" <hpa@zytor.com>
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On Mon, Dec 09, 2002 at 02:15:12PM -0800, H. Peter Anvin wrote:

> > The general idea is that f_fsid contains some random stuff such that
> > the pair (f_fsid,ino) uniquely determines a file.

> This, of course, is the exact POSIX definition of the st_dev part of
> struct stat: (st_dev, st_ino) uniquely identifies the file.

Yes, but the difference is that (st_dev, st_ino) only identifies
the file within a single machine, and may stop working when you
have NFS mounts.

The traditional implementations use st_dev and NFS filehandles
and a hash of the filesystem type.

Andries