On 10/25/2019 5:08 PM, Michael Kjörling wrote:
> The only thing resembling "deprecation" of dd that I'm aware of is the
> recommendation I saw many years ago to not use it to copy potentially
> problematic storage media (for data recovery), but to use ddrescue for
> that purpose instead. The reason for this is that with conv=noerror
> (without which it'd simply abort if it encounters an I/O error), dd
> would simply skip past data in the input that it can't read, but not
> adjust any offsets in the output, which wreaks havoc with anything
> where offsets matter (such as in file system metadata).
Which is where conv=sync,noerror comes in. Of course, I have no freakin'
idea what version of UNIX that came into being. ;)
Ddrescue tries multiple times with different sizes, which dd doesn't do.
Warner