xgDisplay refresh

[Doug Dotson]

I am developing an application that involves updateing a raster file in real-
time.  I would like to have the display on xgDisplay update periodically
with new the new data.  Is there a way to goose xgDisplay into re-reading
and displaying a raster file using an external stimulus such as a signal?
I suspect such a change is simple enough but I thought I'd ask before I
tear into the code.
Thanks,
Doug Dotson
Tate Integrated Systems, L.P.