Re: write verification when using growisofs
In order to do a verifiable write when using cdrecord I follow
1. I first create the iso image of the data on the disk and calculate
its checksum. Then I write the iso image to the CD and delete the iso
image from disk.
2. Using readcd I read the iso image back from the CD
3. Calculate the checksum of this iso image
4. For verification, I compare the two checksums
I am new to growisofs and understand that it does not write
intermediate iso image to disk but rather directly to DVD.
Well, you can as well generate intermediate ISO image and record it with
growisofs -Z /dev/dvd=image.iso. It's even possible to generate
intermediate incremental images and record them with -M
/dev/dvd=image.iso. But the latter works only with sequential recordings
(DVD+R, DVD-R, DVD-RW Sequential) and nothing but tricky. So tricky that
I'd rather not discuss the procedure unless you [or somebody else] can
be really persuasive;-)
> If I have to
write ,say DVD-R, with incremental writes what is the mechanism by which
I can do the verification of each incremental write process. Can it be
done in a manner equivalent to the one I described above or is there a
For multi-session recordings I'd rather recommend to verify integrity of
every file rather than of incremental image. It will work for all
multi-session recordings, DVD+RW, DVD+R, DVD-R, DVD-RW, even DVD-RAM. A.