From owner-freebsd-scsi Mon Aug 28 22:16:43 2000 Delivered-To: freebsd-scsi@freebsd.org Received: from feral.com (feral.com [192.67.166.1]) by hub.freebsd.org (Postfix) with ESMTP id A8DDA37B43C for ; Mon, 28 Aug 2000 22:16:40 -0700 (PDT) Received: from beppo.feral.com (beppo [192.67.166.79]) by feral.com (8.9.3/8.9.3) with ESMTP id WAA25626; Mon, 28 Aug 2000 22:15:44 -0700 Date: Mon, 28 Aug 2000 22:15:41 -0700 (PDT) From: Matthew Jacob Reply-To: mjacob@feral.com To: Greg Lehey Cc: Sam , freebsd-scsi@FreeBSD.ORG Subject: Re: "tape is now frozen" In-Reply-To: <20000829131721.R11422@wantadilla.lemis.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-scsi@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > > I've lost the *exact* position. In fact, I'm not even sure I've lost > the exact position, but I'm prepared to concede that. Within a block > or so I know where I am. > You cannot know that. > > The whole point of rewind, eom or offline is to bring the tape to a > > *known* place. Spacing one filemark is not sufficient. > > Why not? We know we're at the beginning (or end) of a file. I have fifty files of *almost* identical data. If I think I'm at file 43, but I'm at file 42, that's wrong. If tape position has been lost, it's been lost. It's more than a "little bit" pregnant. It's just barely possible to concede that a (successful) report of hardware block position could be construed as "setting location". But this also means that all other notions of file location can not be known any more. > Well, no, I state it above. > > > It has occurred because there was an I/O error, or you're not using > > the tape correctly (fixed block mode and you don't issue the correct > > read size). > > Precisely. But that's not a reason to penalize people by making them > wind from one end of the tape to the other. Argh!!!!! I just plain don't agree, Greg. I'm sorry. If you don't know what the blocksize is, switch to variable mode. Even then- what's the big deal. You're not in the middle of the tape- you're at the front of the tape if you don't know. I really don't want to change this behaviour. It's wrong to allow people to do things that would encourage data lossage. -matt To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message