#include <stdio.h>
#include <time.h>
#include <X11/Xlib.h>

Display *d;
Window w;
Screen s;

int main(void)
{
    XEvent evt;
    char s[80];
    clock_t clk;
    int screen;

    d = XOpenDisplay(NULL);

    printf("%d\n", WidthMMOfScreen(DefaultScreenOfDisplay(d)));

    w = XCreateSimpleWindow(d, DefaultRootWindow(d), 1, 1,
	    500, 375, 0, 0x0000ff, 0xff0000);

    if (! w) {
	printf("Error creating window!\n");
	exit(1);
    }

    XMapWindow(d, w);

    clk = clock();

    while(1) {
	while(XPending(d))
	    XNextEvent(d, &evt);
	if ((clock() - clk) >= 5000000)
	    break;
    }

    XDestroyWindow(d, w);
    XCloseDisplay(d);
}
.