From Mark S:
$ zfs list export/home/marks@Monday
cannot open 'export/home/marks@Monday': operation not applicable to datasets of this type
why do I have to tell it I'm looking at a snapshot when I am explicitly requesting a snapshot? The zfs list code could easy enough check for the @ sign and do the right thing.
$ zfs list -t snapshot export/home/marks@Monday
NAME USED AVAIL REFER MOUNTPOINT
export/home/marks@Monday 1.18M - 1.89G -