blanking DVD+RW

[Chuck Swiger]

Claudio Discepola wrote:
>   I have a quick question about blanking a DVD+RW.  It seems that even
> after I run the "growisofs -Z /dev/cd0=/dev/zero" command the "Disc
> status" is still seen as "complete" instead of "blank". 

Simply using dvd+rw-format doesn't erase all of the previous contents of the 
DVD, whereas overwriting with zeros as you've done will obscure the old data 
reasonably well.

There is a difference between a disk which has never been written to, and a 
disk which has been written full of zeros.  Note that someone with the right 
forensics technology probably could read a zeroed DVD, the same way you can 
read most of the data from a hard drive even after a single erasure pass.

-- 
-Chuck