From owner-freebsd-geom@FreeBSD.ORG  Sun Jan 25 22:28:09 2004
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To: slick <plan_b@videotron.ca>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Sun, 25 Jan 2004 23:09:11 EST."
             <BDENIKJMJKOAJAMDFLDDCECICAAA.plan_b@videotron.ca> 
Date: Mon, 26 Jan 2004 07:27:59 +0100
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cc: hackers@freebsd.org
cc: freebsd-geom@freebsd.org
Subject: Re: code compatibility between normal and geom methods for
	accessingdisk devices 
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In message <BDENIKJMJKOAJAMDFLDDCECICAAA.plan_b@videotron.ca>, slick writes:

>	I wrote an fdisk program which uses several read(2) and write(2).

You program needs to realize that disks have sectors.  You cannot
read a single byte from a disk at a time, you need to read an entire
sector and pick the byte out you want.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.