> I burn DVD/CDs from ISO files. In order to verify the burning is correct, I wrote a script working like this:
> 1. mount the DVD and ISO files onto two mount points
> 2. calculate every file's md5sum in each directory, and save and sort them in two separate files
> 3. compare the above two files.
>
> The above method does work, but too time consuming because of the md5sum calculating. Do you have any suggestion to improve the efficiency?
>
The way I see it, you've got a few choices:
1. Compare ls -lR which won't catch burn issues. But pretty quick.
2. dd the cd and diff or checksum that.
3. Copy the files back to disk and run the checksum there (possibly quicker because the disk shouldn't have time to slow down).
4. The way you're doing it :)
I don't think there are any other options. Though, I'd question your motives here. If you're thinking cheap backup I wouldn't recommend it over tape or just buying tons of the cheapest ($/gig) hdd you can find.