How to interrupt hung boot process?

[Dieter]

Working on updating a amd64 box from 7.0 to 7.1.
A shell script called from rc.local hung.
(Still don't know why, works fine in 7.0, works
fine in 7.1 executed manually once system is up.)
Tried ^C, ^\, ^P and nearly every other key on the
keyboard.  They echo, but nothing will interrupt
the hung process.  I had to press the reset button.

Back in the day, typing ^C on the console would
interrupt the boot process and give you a shell
prompt.  How do I interrupt the boot process
with FreeBSD?

Is there a way to have getty start before running
rc.local?