# First check file tree with beginning-only test image:
timeout 2 genisoimage -r -udf -V "test image" -o test.iso 2BDR 
sudo mount test.iso $media/UDF
find 2BDR |wc
find $media/UDF |wc
sudo umount test.iso

# after successful check, write to disc.
growisofs -use-the-force-luke=spare:none -use-the-force-luke=notray  -overburn -Z /dev/sr1 -speed=4 -r -udf  -V "BD-R-date-comment" 2BDR