How to determine if a DVD is "closed"/finalized?

I have to add a small 50Mb file to DVD. For this I want find unfinilized DVD.
There are more than 20 candidates (DVDs) to be added.
I would like to find small command-line utility for just an answer: Yes, you can add the file to this DVD.
or “No, this DVD already finalized.”
Any idea.
Thanks

Nice andeasy:

nerocmd --discinfo --drivename d: --extended

Unfinalized is not enough!

You need aCD which already has been started as “MULTISESSION CD”