Re: 2.6.0, cdrom still showing directories after being erased

From: Derek Foreman
Date: Tue Feb 03 2004 - 14:37:12 EST


On Tue, 3 Feb 2004, John Bradford wrote:

> Quote from mru@xxxxxx (=?iso-8859-1?q?M=E5ns_Rullg=E5rd?=):
> > John Bradford <john@xxxxxxxxxxxx> writes:
> >
> > >> That's not what he said and, I assure you that if he unmounted
> > >> it there would not be any buffers to flush. Execute `man umount`.
> > >
> > > I think the original poster was referring to the cache on the device.
> > >
> > > I.E.
> > >
> > > mount disc
> > > view contents
> > > unmount disc
> > > erase disc - but don't erase the CD-R drive's cache of the media
> > > mount disc
> > > view old contents of the media from the CD-R drive's cache
> >
> > If that's the case, the drive is broken. We can't help that.
>
> Is it actually a requirement for drives to support anything other than
> a full erase properly? Is the 'fast' erase valid per spec, or does it
> just happen to work on 99% of devices? Is this problem reproducable
> if a full erase is done instead of a fast erase?
>
> I've added the original poster to the CC list.

"Blank" is a single scsi command, 3 bits of the command specify what type
of blanking to perform. So cdrecord isn't doing something devious, it's
well defined in the MMC standard.

Just making cdrecord -eject at the end of the process will probably
workaround what is almost certainly a hardware bug. or just eject the
disc by hand before attempting to re-use it.

I had an old writer that did much the same thing. After burning a disc,
it would still see it as blank until you ejected and reloaded.

to Martin:
Does cdrecord -toc still show a valid toc after you blank the disc?
(definately buggy hardware)

And does ejecting and reloading the disc make things work as expected?
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