#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <X11/Xlib.h>

int main() {
  Display *d;
  Window w;
  XSetWindowAttributes attr;
  
  d = XOpenDisplay(NULL);
  if(d == NULL) abort();

  attr.background_pixel = BlackPixelOfScreen(DefaultScreenOfDisplay(d));
  attr.event_mask = StructureNotifyMask | ExposureMask;
  attr.override_redirect = True;
	
  w = XCreateWindow(d,DefaultRootWindow(d),0,0,100,100,0,CopyFromParent,InputOutput,CopyFromParent,
                    CWBackPixel|CWEventMask,&attr);
  XMapWindow(d,w);
  XFlush(d);
  for(;;) {
    XEvent e;
    XNextEvent(d,&e);
    switch(e.type) {
      case Expose:
        printf("Expose\n");
        break;
      case ConfigureNotify: {
        XConfigureEvent *ce = (XConfigureEvent*) &e;
        printf("ConfigureNotify: width: %d height: %d\n",ce->width,ce->height);
        printf("Rendering...\n");
        sleep(1);
        printf("Done rendering\n");
        break;
      }
    }
  }
}