[Info-vax] LDDriver, Tools to create ISO

[John H. Reinhardt]

On Mar 18, 9:17 pm, David J Dachtera <djesys... at spam.comcast.net>
wrote:
> JF Mezei wrote:
>
> > David J Dachtera wrote:
>
> > > The VMS equivalent is:
>
> > > $ MOUNT/FOREIGN ddcu:
> > > $ COPY ddcu: DISK_IMAGE.ISO
> > > $! Copy completes with an error complaining about
> > > $! illegal block number, but the target file is complete
> > > $! and intact.
> > > $ DISM ddcu:
>
> > Wouldn't the following more accurately do a "block by block" copy:
>
> > LD CREATE myiso.iso/size=xxxxxx
> > LD CONNECT myiso.iso LDA1:
> > BACKUP/PHYSICAL dua0: LDA1:
>
> I don't know as I would say "more accurately", though I expect it would
> finish with a success status. "block by block" copy is "block by block"
> copy - there's really nothing to screw up. Think: unit record I/O.
>
> BACKUP/PHYSICAL output savesets are not "disk images" and apparently
> cannot be used as such. On my little Alpha, I just tried an 870932 block
> AOL CD of old and it produced a 972909 block saveset.
>
> Also, both input and output devices probably need to be MOUNTed
> /FOREIGN. You could automate the LD CREATE part by stat'ing the input
> device to get it's size (F$GETDVI( "ddcu:", "MAXBLOCK" )), perhaps
> rounding that up to the next multiple of 8, and then maybe add another 8
> blocks for over-burn in case you decide to create a CD-R from it.
>
> I don't have an Alpha with a DVD drive. So, I can't speak to that.
>
> D.J.D.

Mounting /foreign is the way to go.  No BACKUP saveset (physical or
otherwise) is going to usable as disk image due to the CRC and other
error checking information stored.