From owner-freebsd-questions@FreeBSD.ORG Wed Jan 7 13:08:24 2004 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id F075616A4CE for ; Wed, 7 Jan 2004 13:08:24 -0800 (PST) Received: from mta02-svc.ntlworld.com (mta02-svc.ntlworld.com [62.253.162.42]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1D8DF43D1F for ; Wed, 7 Jan 2004 13:08:23 -0800 (PST) (envelope-from scott@fishballoon.org) Received: from llama.fishballoon.org ([81.104.195.124]) by mta02-svc.ntlworld.comESMTP <20040107210803.YJEF29762.mta02-svc.ntlworld.com@llama.fishballoon.org>; Wed, 7 Jan 2004 21:08:04 +0000 Received: from tuatara.fishballoon.org ([192.168.1.6]) by llama.fishballoon.org with esmtp (Exim 4.24; FreeBSD) id 1AeKtT-000Pag-Lb; Wed, 07 Jan 2004 21:07:11 +0000 Received: (from scott@localhost) by tuatara.fishballoon.org (8.12.10/8.12.10/Submit) id i07L7A7F000554; Wed, 7 Jan 2004 21:07:10 GMT (envelope-from scott) Date: Wed, 7 Jan 2004 21:07:09 +0000 From: Scott Mitchell To: Hendrik Hasenbein Message-ID: <20040107210709.GA504@tuatara.fishballoon.org> References: <02b401c3d2d7$81439f40$8464a8c0@ovirt.dyndns.ws> <20040107081315.0786de1e.doublef@tele-kom.ru> <20040107093611.0a7983df.doublef@tele-kom.ru> <20040107094356.V24917@zoraida.natserv.net> <3FFC3C6B.3020809@techfak.uni-bielefeld.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3FFC3C6B.3020809@techfak.uni-bielefeld.de> User-Agent: Mutt/1.4.1i X-Operating-System: FreeBSD 4.9-STABLE i386 cc: Sergey 'DoubleF' Zaharchenko cc: freebsd-questions@freebsd.org cc: "W. Sierke" Subject: Re: How to create .iso file image of cdrom (atapi)? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 07 Jan 2004 21:08:25 -0000 On Wed, Jan 07, 2004 at 06:05:47PM +0100, Hendrik Hasenbein wrote: > Francisco Reyes wrote: > >Other than speed is there any consideration about the buffer size? > I assume you are referring to the 'bs=2048' argument to dd. > The argument 'bs=2048' sets the block size to be used for the device. > You can't use another value for cdrom drives than 2048 except you are > able to change the blocksize on the drive. Some can be jumpered for 512 > per block, but there is no need to do that. If you use another value for > bs the operation will fail on a cdrom drive. Well, you can use a bs value that is a multiple of 2048 (like the 64k in my previous example). Using a larger block size will generally speed up the transfer, up to a point. Scott -- =========================================================================== Scott Mitchell | PGP Key ID | "Eagles may soar, but weasels Cambridge, England | 0x54B171B9 | don't get sucked into jet engines" scott at fishballoon.org | 0xAA775B8B | -- Anon