#include <xcb/xcb.h>
#define XK_LATIN1
#include <xcb/xcb_keysyms.h>
#include <X11/keysymdef.h>
#include <stdio.h>
#include <stdlib.h>

int
main ()
{
  xcb_connection_t *conn;

  conn = xcb_connect (NULL, NULL);

  xcb_key_symbols_t * keysyms = xcb_key_symbols_alloc(conn);

  xcb_keycode_t * keycodesPtr = xcb_key_symbols_get_keycode(keysyms, XK_space);

  const xcb_setup_t* setup = xcb_get_setup(conn);

  xcb_screen_iterator_t screens = xcb_setup_roots_iterator(setup);
  int screensCnt = screens.rem;

  for (int i=0; i<screensCnt; i++) {

      xcb_void_cookie_t rez_grab = xcb_grab_key(conn, 1, screens.data->root, XCB_MOD_MASK_ANY, keycodesPtr[0], XCB_GRAB_MODE_ASYNC, XCB_GRAB_MODE_ASYNC);

      const static uint32_t values[] = { XCB_EVENT_MASK_EXPOSURE | XCB_EVENT_MASK_BUTTON_PRESS };

      xcb_change_window_attributes (conn, screens.data->root, XCB_CW_EVENT_MASK, values);

      xcb_screen_next(&screens);
  }

  xcb_flush(conn);

  // start event loop
  while (1) {
      xcb_generic_event_t *ev = xcb_wait_for_event(conn);

      if (ev && ((ev->response_type & ~0x80) == XCB_KEY_PRESS))
      {
          xcb_key_press_event_t *kp = (xcb_key_press_event_t *)ev;
          printf ("Got key press %d\n", (int)kp->event);
      }

      if (ev != NULL) {
          free(ev);
      }
  }

  return 0;
}