From owner-freebsd-questions@FreeBSD.ORG  Thu Nov 15 21:32:49 2012
Return-Path: <owner-freebsd-questions@FreeBSD.ORG>
Delivered-To: freebsd-questions@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52])
 by hub.freebsd.org (Postfix) with ESMTP id E0F04111
 for <freebsd-questions@freebsd.org>; Thu, 15 Nov 2012 21:32:49 +0000 (UTC)
 (envelope-from rfg@tristatelogic.com)
Received: from outgoing.tristatelogic.com (segfault.tristatelogic.com
 [69.62.255.118])
 by mx1.freebsd.org (Postfix) with ESMTP id BB1688FC0C
 for <freebsd-questions@freebsd.org>; Thu, 15 Nov 2012 21:32:49 +0000 (UTC)
Received: from segfault-nmh-helo.tristatelogic.com (localhost [127.0.0.1])
 by segfault.tristatelogic.com (Postfix) with ESMTP id 093E75081D
 for <freebsd-questions@freebsd.org>; Thu, 15 Nov 2012 13:32:47 -0800 (PST)
To: freebsd-questions@freebsd.org
Subject: Re: Advanced Format Drive ?
In-Reply-To: <50A4F2C8.5040308@qeng-ho.org>
Date: Thu, 15 Nov 2012 13:32:47 -0800
Message-ID: <25307.1353015167@tristatelogic.com>
From: "Ronald F. Guilmette" <rfg@tristatelogic.com>
X-BeenThere: freebsd-questions@freebsd.org
X-Mailman-Version: 2.1.14
Precedence: list
List-Id: User questions <freebsd-questions.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/freebsd-questions>, 
 <mailto:freebsd-questions-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-questions>
List-Post: <mailto:freebsd-questions@freebsd.org>
List-Help: <mailto:freebsd-questions-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
 <mailto:freebsd-questions-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 15 Nov 2012 21:32:49 -0000


In message <50A4F2C8.5040308@qeng-ho.org>, 
Arthur Chance <freebsd@qeng-ho.org> wrote:

>On 11/15/12 12:41, Ronald F. Guilmette wrote:
>>> -b is the beginning block of a partition.  34 is a magic value, the size
>>> of a standard GPT partition table.
>>
>> It probably wouldn't have hurt anything to mention that in the gpart man
>> page.
>>
>> And what about 162?  Is that magic too?  If so, how?  I seriously do not
>> know.
>
>The man example should be taken as a whole. You've got
>
>/sbin/gpart add -b 34 -s 128 -t freebsd-boot ad0
>
>which gives you a 128 block partition starting at block 34, so the next 
>free block is 162, and the next partition is explicitly started there in
>
>/sbin/gpart add -b 162 -s 1048576 -t freebsd-ufs ad0
>
>No magic, just arithmetic. :-)

Ah!  Silly me!  Thank you.  (I did miss that.)


Regards,
rfg