how to determine from the command line whether a DVD is encrypted
I am currently ripping a bunch of DVDs. Some are encrypted, and some are not. My method for ripping a DVD depends on whether or not it is encrypted, so I am looking for a command-line method to determine if a DVD is encrypted or not.
My current way to detect whether a DVD is encrypted or not is that if it is encrypted, then running
dd if=/dev/sr0 of=file.iso results in "Input/output error". I'm looking for a better way.