(I've never heard whether the 'current' in current-users is an adjective for
   'users' or 'source-sode'.)

The mailing list info says:

`This is a forum for all people using an up-to-date version of the
NetBSD-current source tree.  [...]'

But that's okay; you're still welcome.  B-)

   I'm running a 1.0 system and came across this earlier today. (I'm writing
   this in 'vi' and I'm about to type '!$date^M' IN command mode. )

   stty: TIOCGETD: Operation not supported
   Wed Dec 14 11:34:17 EST 1994

It sounds like one of your shell startup files is running stty(1) on
the pipe.  Since a pipe is not a terminal, none of the TIOC* ioctls
will work.