How do I unmount /usr?

[Ed Ravin]

Ye gods and little fishes!  Even the simplest things don't work
sometimes.  Here I am, trying to reconfigure the /usr filesystem
on my RS/6000 Power?Server 520 and AIX 3.1.5 freshly re-installed...

# init 0
# ps -ef
 [ps shows exactly three processes -- ksh, init, and ps]
# pwd
/
# unmount /usr
/dev/hd2 : device busy

I also tried this under sh instead of ksh, in case ksh was checking
MAILPATH or some such silly thing.  No luck.

What do I have to do to unmount /usr, say "swordfish" somewhere?  It's
about the only thing I haven't tried.
-- 
Ed Ravin            | I'm sorry, sir, but POSTAL REGULATIONS don't allow
cmcl2!panix!eravin  | PLASTIC tape over PAPER tape and NYLON cord on an
philabs!trintex!elr | 86 inch girth to LITHUANIA...
+1 914 993 4737     |