Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 8 Nov 2001 15:12:03 +0000
From:      Simon Dick <simond@irrelevant.org>
To:        Nils Holland <nils@tisys.org>
Cc:        Stijn Hoop <stijn@win.tue.nl>, freebsd-questions@freebsd.org
Subject:   Re: dd and cat - Did I miss something?
Message-ID:  <20011108151203.B8435@irrelevant.org>
In-Reply-To: <20011108141503.P1041-100000@jodie.ncptiddische.net>; from nils@tisys.org on Thu, Nov 08, 2001 at 02:18:05PM %2B0100
References:  <20011108123825.E94394@pcwin002.win.tue.nl> <20011108141503.P1041-100000@jodie.ncptiddische.net>

next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, Nov 08, 2001 at 02:18:05PM +0100, Nils Holland wrote:
> On Thu, 8 Nov 2001, Stijn Hoop wrote:
> 
> > On Thu, Nov 08, 2001 at 12:16:57PM +0100, Nils Holland wrote:
> > > Hi folks,
> > >
> > > I just wanted to copy a data CD. So I thought I'd first read it out. After
> > > I had put the CD into my ATAPI CD-ROM drive, I issued the following
> > > command:
> > >
> > > dd if=/dev/acd0a of=cdimage
> > >
> > > But it didn't work. I received a message saying "acd0a - Invalid
> > > Argument".
> > >
> > > Next, I tried something different, namely:
> > >
> > > cat /dev/acd0a | dd of=cdimage
> > >
> > > and that did work! Any clues why my first attempt (only using dd and not
> > > cat) failed?
> >
> > You should use /dev/acd0c - the 'c' partition means the whole disk. CD's
> > don't have the concept of partitions, so there are no {a,b,...} partitions.
> > Why the second attempt worked is a mystery to me...
> 
> Let's make some even bigger mystery out of it: dd if=/dev/acd0c of=cdimage
> also fails, again with the "acd0c - Unknown Argument" message. Of course,
> the second method still works after replacing acd0a with acd0c...
> 
> I'm running 4.4-Stable (as of last Saturday) here, and I think I remember
> that some time in the past I had no such problems with dd. If anyone has
> a clue what I'm doing wrong or what's going on here, I'd like to hear
> about it!

How about trying something like this:
dd bs=2048 if=/dev/acd0c of=cdimage.iso

it works for me.

-- 
Simon Dick					simond@irrelevant.org
"Why do I get this urge to go bowling everytime I see Tux?"

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-questions" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20011108151203.B8435>