How come Red Hat  has two versions of rc.local, one in /etc and another 
in /etc/rc.d? How come I can't get either one to work?

I recently switched from tcsh to zsh. Not that I have anything against 
tcsh. It's still the best interactive shell out there. Anyway, in TC if 
you change something in one of your startup scripts, you can type 
'rehash' and it's as if you logged in again. The shell re-initializes 
itself based on the new scripts. How do you do this in zsh?