I tried dump with the following arguments
-a          force to the end of reading
-b 2        2kB block size
-f ..       write output to file
/dev/cd0a   file to read

This is what I got.

bash-2.05b# dump -a -b 2 -f filename.iso /dev/cd0a
  DUMP: bad sblock magic number
  DUMP: The ENTIRE dump is aborted.

I also tried without the -a and -b options. Same deal.

Any ideas?




Stefan Schumacher wrote:
> * Brian Rose (lists@brianrose.net) wrote:
> 
>>I'm backing up a game I purchased recently and I am having some issues. I 
>>am currently using good ole dd in the following way...
>>
>>dd if=/dev/cd0a of=filename.iso bs=2k
> 
> 
> [dd dies]
> 
> 
>>dd transfers 1.6 megabytes before dying. It should have 686,510,080 bytes 
>>(according to my Windows box). I found some information on the net that 
>>suggests that multi-session CD's may not work with this method, but there 
>>was no information about how to make it work.
> 
> 
> Could it be that there is a kind of copy protection used on that CD? 
> Have you tried dump(8) to create a backup? dump is really strong and IMO the
> best backup tool.
> 
> --
> Wenn ich sehe, in Sachsen-Anhalt, das sind auch immer die Leute, 
> die mit offenen Haenden herumlaufen"
> 
> ein gewisser Edmund Stoiber