From the NannyMUD documentation

LAST CHANGE

2000-12-18

COMMAND

NAME
        areaclosed - check if an area is closed


SYNTAX
	areaclosed 'path'

DESCRIPTION
	This command checks with the area daemon if an area is considered
	open or closed. If no 'path' is given then it will print all areas
	that are currently closed, otherwise it will tell you if the 'path'
	you have entered is closed.


NOTE
	Old areas are not handled by the area daemon; this will lead to some
	inconsistencies.