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From: "Ronald F. Guilmette" <rfg@tristatelogic.com>
To: freebsd-questions@freebsd.org
Subject: Re: A question about fsck and the -t option
In-Reply-To: <533C40BF.2010907@cyberleo.net>
Date: Wed, 02 Apr 2014 16:00:46 -0700
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In message <533C40BF.2010907@cyberleo.net>, 
CyberLeo Kitsana <cyberleo@cyberleo.net> wrote:

>A glance at the source code[1] suggests that {fsck} attempts to infer the
>type from the fstab, and then the BSD disklabel.

Based upon my limited perusal/skimming of the fsck man page, this appears
to be undocumented behavior.

I shall be filing a documentation PR on this, because I'm a firm believer
that important aspects of behavior should be documented.

>It does not appear to
>attempt a guess from the filesystem magic itself.

Should it perhaps do so?

The particular filesystem that wanted to check yesterday was most definitely
_not_ listed in my /etc/fstab file.  But that was not an oversight.  That was
by intent.

Also and separately, please correct me if I am wrong, but aren't BSD style
partition labels going the way of the dinosaur, now that we have GPT
partitioning available?