From owner-freebsd-questions@FreeBSD.ORG  Wed May 14 06:09:18 2003
Return-Path: <owner-freebsd-questions@FreeBSD.ORG>
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 6623537B40C
	for <freebsd-questions@freebsd.org>;
	Wed, 14 May 2003 06:09:18 -0700 (PDT)
Received: from smtp0.adl1.internode.on.net (smtp0.adl1.internode.on.net
	[203.16.214.194])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 2962F43FB1
	for <freebsd-questions@freebsd.org>;
	Wed, 14 May 2003 06:09:17 -0700 (PDT)
	(envelope-from Malcolm.Kay@internode.on.net)
Received: from beta.home (ppp364.sa.padsl.internode.on.net [150.101.245.107])
	h4ED9FMO096449	for <freebsd-questions@freebsd.org>;
	Wed, 14 May 2003 22:39:16 +0930 (CST)
Content-Type: text/plain;
  charset="us-ascii"
From: Malcolm Kay <Malcolm.Kay@internode.on.net>
Organization: At home
To: freebsd-questions@freebsd.org
Date: Wed, 14 May 2003 22:39:15 +0930
User-Agent: KMail/1.4.3
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
Message-Id: <200305142239.15266.Malcolm.Kay@internode.on.net>
Subject: burncd -- possible problem
X-BeenThere: freebsd-questions@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: User questions <freebsd-questions.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/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: Wed, 14 May 2003 13:09:19 -0000

I'm not sure whether I have a problem burning CD-Rs -- certainly
I don't understand what I observe.

The OS is FreeBSD 4.7-release.

I take a commercial CD-ROM and copy it as an image with:
# cp /dev/acd1c natins.cd
which creates the file natins.cd of around 673400*1024 bytes=20
without any apparent problem. (I can't remember the exact size
but was certainly a multiple of 1024).

# md5 natins.cd
and
# cat /dev/acd1c | md5
produce identical results.

Now inserting a blank CD-R:
# burncd -f /dev/acd1c data natins.cd fixate
runs apparently normally and without error.

But now
# cat /dev/acd1c | md5
produces and IO error and a different checksum

# cp /dev/acd1c natins.back
produces the same IO error and a file 8*1024 bytes
shorter than natins.cd.

If I strip off the last 8k from natins.cd and compare the
result with natins.back I find they are the same.

When I look at the last 8*1024 bytes stripped from natins.cd I=20
find these are all zero (ie NUL).

Re-running burncd on a new CD-R blank repeats the result=20
exactly; i.e. IO error 8k short of the size of the original but the
rest matching.

As a mounted cd9660 file system the copy appears normal and=20
the visible files test identical to those on the original.

Questions:
Is what I'm observing normal when writing with burncd?
Do I have a hardware problem?
Is this due to some bug in burncd?

Should I worry about this or just ignore?

Malcolm Kay