How do I stop/restart shell's?

[jim at easby.durham.ac.uk]

I'm trying to stop all (well most) processes on a server so I can do an
effective single user dump, then restart them.  Sending a SIGSTOP to a csh
disconnects, sending it to a su'd shell stop the shell, but then sending a
SIGCONT causes a HANGUP after stating the the pgrp has been reset, then
reset again.  Sending a SIGSTOP then a SIGCONT using /bin/kill works for
su'd shell, so SUN must do something in /bin/kill more than just a kill(2)
(ULTRIX does just do a kill(2) - nothing fancy in ULTRIX).  

So can anyone help?

Jim.

PS - forgot to mention, running 3.4 on a 3/280.