Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 7 May 1996 11:33:15 +0930 (CST)
From:      Michael Smith <msmith@atrad.adelaide.edu.au>
To:        terry@lambert.org (Terry Lambert)
Cc:        msmith@atrad.adelaide.edu.au, terry@lambert.org, rnordier@iafrica.com, hackers@FreeBSD.org
Subject:   Re: dosfsck anyone?
Message-ID:  <199605070203.LAA18048@genesis.atrad.adelaide.edu.au>
In-Reply-To: <199605070122.SAA22485@phaeton.artisoft.com> from "Terry Lambert" at May 6, 96 06:22:39 pm

next in thread | previous in thread | raw e-mail | index | archive | help
Terry Lambert stands accused of saying:
> 
> > > 1)	There is a limit on the number of entries in "/" on DOS FS's
> > > 	that isn't enforced on subdirectories.
> > > 
> > > 	a)	If you don't use "lost+found", you risk exceeding
> > > 		this limit.
> > 
> > I don't think _not_ using it is an option.
> 
> Works not having one under DOS...

"works" in what context?  If you mean "chkdsk works without one", then
I suggest you consider what happens when it tries to create too many
.chk files.  These aren't actually much use anyway.  Using a heirachy
under a lost+found directory gives you some chance of segregating the
victims of seperate corruptions, which may help a little in reconstruction.

I think that most people faced with serious FAT FS corruption would just
blow it away and restore/reinstall, so the aim is not to intuit magical
details, but just to get the FS in a consistent state.

> I liked the idea of handling crosslinks by deconstruction rather
> than lost+found.

The problem being that the deconstruction is almost certain to be wrong.

> Sorry; I just got off a project doing a network redirector for
> Win95, and they were all faked.  Shouldn't have assumed.  8-(.

Fair enough 8)  The only useful think about '..' is that it points to the
starting cluster of the parent directory.

> What about ".." in "/"?

There isn't one 8)

> > > How will these anomolies be introduced?  By (in violation of usage
> > > semantics) caching?
> > 
> > No.  By the potential operation of the 'dosfsck' program, as stated in
> > the preceeding paragraph.
> 
> How does a cross-link get created is what I was asking...?

Ah.  I don't think we're expecting any to be created by the new DOSFS, but
you'll get them under DOS if 'smartdrive' loses its marbles, or if a 
program with a rogue pointer scribbles on DOS' buffers, or if some twonk
hits RESET while the FAT is being updated, or if DOS/Win/whatever 
takes a dive while the FAT is in an inconsistent state.

None of the MS FAT filesystem drivers seem to place much emphasis on
maintaining filesystem consistency.

> 					Terry Lambert

-- 
]] Mike Smith, Software Engineer        msmith@atrad.adelaide.edu.au    [[
]] Genesis Software                     genesis@atrad.adelaide.edu.au   [[
]] High-speed data acquisition and      (GSM mobile) 0411-222-496       [[
]] realtime instrument control          (ph/fax)  +61-8-267-3039        [[
]] Collector of old Unix hardware.      "Where are your PEZ?" The Tick  [[



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199605070203.LAA18048>