Subject: Re: cd-rw
To: Thor Lancelot Simon <>
From: Curt Sampson <>
List: tech-kern
Date: 02/16/2000 15:22:14
On Wed, 16 Feb 2000, Thor Lancelot Simon wrote:

> On Tue, Feb 15, 2000 at 10:05:10PM -0800, Chris G. Demetriou wrote:
> > "Kevin P. Neal" <> writes:
> > > Works just fine. Only odd thing is that if I dd a CD in the burner to
> > > a file, the drive fails to stop reading at the end of the CD, returning
> > > garbage or whatever to the dd process which will never stop. 
> > > 
> > > I can dd just fine in my RRD43, so it's not so much a big deal. 
> > 
> > raw device, or block device?
> > 
> > I think i _might_ have seen that on a block device recently (on i386),
> > but i don't recall all the details and didn't have time to track it
> > down at the time...
> I think this is another flavor of the same old bug we've had for ~ever
> with 'dd' from raw SCSI devices: when you hit the end of the device,
> instead of EOF and a short read -- as you'd expect, and so 'dd' or 'cat'
> would actually work right! -- a SCSI command is issued to read past the
> end, you get an error back, and the user program splodes.

I find it to be controller dependent. It happens on my CD-RW on an
AHA-2940UW, but not when I put the same drive on an NCR 53c810.

Curt Sampson  <>   917 532 4208   De gustibus, aut bene aut nihil.
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