Getting the Size of the Screen

Date: 6 April 1997
Author: Christopher Kohlhoff

All you have to do is

screenWidth = GetSystemMetrics(SM_CXSCREEN);
screenHeight = GetSystemMetrics(SM_CYSCREEN);

or if you are using OWL 5 you can use

#include <winsys/uimetric.h>

screenWidth = TUIMetric::CxScreen;
screenHeight = TUIMetric::CyScreen;