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Date: Sat, 8 Jul 2006 18:46:06 +0100
From: Christoph Hellwig <hch@infradead.org>
To: Sam Leffler <sam@errno.com>
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Cc: Craig Rodrigues <rodrigc@crodrigues.org>, freebsd-current@freebsd.org,
	freebsd-arch@freebsd.org
Subject: Re: [RFC] mount can figure out fstype automatically
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On Sat, Jul 08, 2006 at 09:05:51AM -0700, Sam Leffler wrote:
> Linux has -t auto; haven't looked at how it works.

It's implemented in mount(8).  It has a table of magic numbers and offsets
and tries all of them in a well defined order.  If everything fails it
tries a few heuristics whether the filesystems might be a FAT filesystem
as thos don't have magic numbers.