7 Apr
2015
7 Apr
'15
6:14 a.m.
On 07/04/2015 11:21, Johnny Billquist wrote:
Sp, to get to the meat of it. No, bad blocks are not
replaced, or mapped
away, or faked. The drive and controller can detect bad blocks, and when
you try to read one, you'll get an error back. Drivers try a few times,
and then give up, giving an error back to the user program.
You should not try anything different.
Absolutely.
Copying RL disks with a block by block copy is not
something you'd do.
You'd mount the disk and copy the contents.
Actually COPY/DEV under RT-11 is commonly used, especially for non-RT-11
packs. I can't remember what RSX does, but RT-11 /does/ deal with the
bad block table, by not copying the last track, and copying remapped
blocks. But in general, under other OSs, yes, not a good idea. It
would be like using dd in Unix to copy an entire device, including the
disk label, rather than the partitions.
--
Pete
Pete Turnbull