[Info-vax] Backup TK50 tapes

[glen herrmannsfeldt]

Bill Gunshannon <billg999 at cs.uofs.edu> wrote:

(snip)
>> I love dd and all, but it THROWS AWAY BLOCK STRUCTURE and leaves you with
>> a byte stream.  The block structure is important on tapes.
 
>> Don't use dd to image tapes!
 
> Unless you do each file individually.  :-)
> That was how the Ultrix-11 boottape got trashed and stayed that
> way until correct bl;ocking could be rediscovered and reimplemented.

For tape to tape copy, yes, you have to do it individually.

For tapes with fixed length records, different lengths for each file, 
it could be done with multiple dd and remembering the lengths.

-- glen