On 11Sep2018 10:24, JD <jd1008(a)gmail.com> wrote:
On 09/11/2018 04:14 AM, Dave Mitchell wrote:
>On Tue, Sep 11, 2018 at 10:19:44AM +0800, Ed Greshko wrote:
>>Are you using only "dd" or are you also using "tar"? I only
ask since I've not seen
>>the message coming from "dd" but recall seeing it from "tar".
>To expand on that:
>
>
> $ strings `which dd` | grep shrank
>
> $ strings `which tar` | grep shrank
> %s: File shrank by %s bytes; padding with zeros
> ...
>
>
>and presumably the warning means that between stat()ing the file and
>opening it and reading its contents, the size of the file got smaller.
>
>So I think the OP is doing more than just 'dd'ing the raw DVD.
Sorry, I did respond and explained my mistake
to another responder that it was my bad.
I was TARing and I explained the commands I used.
Have we considered that (a) the mount might lie about the VOB size (I'm
assuming it was a VOB file from the size - they're generally around 1GB in
size) or that (b) tar got a zero byte read when reading the file (filesystem
bug? I/O error on the disc? DVD CSS stuff screwing with the data?)
The reason for the padding is that tar writes a header with the file size
before the file content, so it needs to pad.
Regarding the DVD CSS stuff: I seem to recall from long ago that reading a CSS
DVD without the libdvdcss stuff to arrange decoding produced read issues, not
just garbled data. This might be that.
Try running wc or something against the problematic file, see if it reads the
whole thing. Even "cat >/dev/null <the-file" might be informative.
CHeers,
Cameron Simpson <cs(a)cskk.id.au>