From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ftp.linux.org.uk>
Subject: Re: Adding subroot information to /proc/mounts, or obtaining that through other means
Date: Wed, 20 Jun 2007 22:03:43 +0100
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Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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To: "H. Peter Anvin" <hpa@zytor.com>
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On Wed, Jun 20, 2007 at 01:57:33PM -0700, H. Peter Anvin wrote:
> ... or, alternatively, add a subfield to the first field (which would
> entail escaping whatever separator we choose):
> 
> /dev/md6 /export ext3 rw,data=ordered 0 0
> /dev/md6:/users/foo /home/foo ext3 rw,data=ordered 0 0
> /dev/md6:/users/bar /home/bar ext3 rw,data=ordered 0 0

Hell, no.  The first field is in principle impossible to parse unless
you know the fs type.

How about making a new file with sane format?  From the very
beginning.  E.g. mountpoint + ID + relative path + type + options,
where ID uniquely identifies superblock (e.g. numeric st_dev)
and backing device (if any) is sitting among the options...