As user: swap capslock/cntrl?

[Edward J Young <eyoung@linus.cudenver.edu>]

How do I swap the capslock and control keys on a standard PC keyboard as a
user only?  (not as root)

I need to do this so I don't get Carpel Tunnel from straining to hit the
control key when running emacs all the time. 

Since this is a system at Univ. of Colorado, and I'm not root, I need to
do it in user space. 


Thanx, 

Ed Young