26 Oct
2019
26 Oct
'19
4:54 a.m.
On Fri, Oct 25, 2019, 3:35 PM Arthur Krewat <krewat(a)kilonet.net> wrote:
On 10/25/2019 5:08 PM, Michael Kjörling wrote:
Ddrescue tries multiple times with different sizes, which dd doesn't do.
Warner
art k.
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. ;)