Porting from Sun to SGI

[Tod Fontana]

I am interested in the pleasures and pitfalls of porting C code from a 
Sun station with three Verdix (?) enhancement boards to an SGI station.
The code I am interested in has Sun Phigs and Sun windowing packages to
handle stick map and imagery presentation.  How portable are any of these
packages to a more standard Phigs (or Phigs to GL library) and X-windows
type packages that run on an SGI system?  Will it be better to start over
from scratch?  

I don't seem to be getting every response posting on the net, so either
email me a response or double post it to the net.

Thank you for any input.