/* cc -Wall -g XRandR.c -o XRandR -lX11 `pkg-config --libs xrandr` */
#include <X11/Xlib.h>
#include <X11/extensions/Xrandr.h>
#include <stdio.h>

int
main(void)
{
  Display *display;
  int screen;
  Window root;
  
  int x, y, i, j;
  unsigned int width, height, border_width, depth;

  if( (display = XOpenDisplay(":0.0")) == 0 ) {
    fprintf( stderr, "Could not open X display\n" );
    return 1;
  }

  screen = DefaultScreen( display );

  XGetGeometry( display, RootWindow( display, screen ), &root,
                &x, &y, &width, &height, &border_width, &depth );

  fprintf( stdout, "root = %d x = %d y = %d width = %d height = %d "
                   "border_width = %d depth = %d\n", (int)root,
                x, y, width, height, border_width, depth );

  XRRScreenResources * res = XRRGetScreenResources(display, root);
  for(i = 0; i < res->noutput; ++i)
  {
    XRROutputInfo * output = XRRGetOutputInfo( display, res, res->outputs[i] );
    for ( j = 0; j < output->ncrtc; ++j)
    {
      XRRCrtcGamma * gamma = XRRGetCrtcGamma( display, output->crtcs[j] );

      fprintf( stdout, "output %d: crtc %d: gamma size: %d\n", i, j, gamma->size);

      XRRFreeGamma( gamma );
    }
    XRRFreeOutputInfo( output );
  }

  XRRFreeScreenResources(res); res = 0;

  return 0;
}