#include <graphics.h> int getwindowwidth(void);
/* getwindowwidth example */ 
#include <graphics.h>
int main(void)
{
   int w_left, w_right;
   int width; // Total width of w_left;
   // Make two windows, side by side */
   w_left = initwindow(300, 200);
   width = getwindowwidth( );   
   w_right = initwindow(300, 200, width, 0);
   /* clean up */
   getch();
   closegraph();
   return 0;
}