On Tue, 16 Jun 2015, Always Learning wrote: > But my point was M$ DOS partitions, not being GPT partitions, can have > UUIDs. The original poster appeared to suggest that was not possible. No, the partition there does not have a UUID. Run fdisk, create a partition, dd if=/dev/zero of=/dev/sda4 blkid You'll see no UUID, as the partition does not provide a UUID, and there's nothing on it to provide a UUID. Format it, or make some swap space or whatever, and you get a UUID. > When I think I am mounting a M$ DOS partition, am I mounting a real > partition or merely 'the file system' within that partition ? Some may > think one can't have one without the other. You never mount a partition, only a filesystem. The partition merely points you to where the filesystem is. jh