fsck on FAT32 filesystem?

Robert Bonomi bonomi at mail.r-bonomi.com
Sun Jul 22 21:00:27 UTC 2012

> From: "Michael Ross" <gmx at ross.cx>
> Date: Sun, 22 Jul 2012 19:06:04 +0200
> On Sun, 22 Jul 2012 17:08:56 +0200, Bruce Cran <bruce at cran.org.uk> wrote:
> Microsoft's format.exe can zero a volume, at least in the newer (>2008)  
> versions:
> /p:<passes> : Zeros every sector on the volume for the number of passes  
> specified.

Early versions of format (until the addition of the '/Q' switch) always over-
wrote the entire disk.  this was how it found the initial 'bad sectors' to
be so marked in the FAT.  As disk capacities increased, the bad block check
took increasingly longer amounts of time.  Hence, along with bad-block
handling (mapping and substitution) moving into the drive electronics,
the introduction of the '/Q' option -- whereby format just overwrote the
fat and root diretory, putting all the data blocks on the free list.

I haven't had occasion to dissect a copy of format in years, I don't know
if it still defaults to one write attemptto every sector on the disk.

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