HELP: how to autologin at boot time?

[Steve Harris]

We have a problem which somebody MUST already have solved.

Our application uses a Sun workstation as the control console for a
real-time control system.  When the system is powered up, the Sun boots as
usual, eventually leading to the unix login prompt.  The operator logs in
as "operator" and the .login and .cshrc scripts start up suntools and run
the control system.  (If it matters, we currently are running SunOS 3.5;
we plan to upgrade to 4.0.3 by the end of the year.)

What we want to do is to eliminate the need for the operator to type
"operator" at the login prompt.  We want the system to do an autologin and
thereby automatically to start the control system.  However, we want to be
in the same suntools environment as we currently have, i.e., we still need
to be able to open windows and have the user id default to operator.

I assume this will involve adding a script "/etc/rc.ctrlsys" which will be
run as a final step in /etc/rc.  But I don't know how to simulate a user
login at that level.  Surely somebody else is doing this already!
Suggestions/pointers to useful ideas gratefully accepted.

Steve Harris -- Eaton Corp. -- Beverly, MA -- uunet!etnibsd!vsh