Asking for root passwd when booting single user?

[Danielle Heinzer]

I have added an entry in any clients passwd files to allow the normal
users to halt their system, when they don't need it.

I would like to avoid that someone boots in single user mode, by entering
'b -s' on prom command line.

How can I set the system to ask for the root passwd, when booting single
user ?

Danielle Heinzer
ESA Computer Department/Computer Services
European Space Operations Centre
Robert-Bosch-str. 5
6100 Darmstadt
West-Germany
Tel int : 49-6151-886540