rem: if (XGetWindowProperty(dpy, window, _XA_WM_CLIENT_LEADER, 0, sizeof(Window), False, AnyPropertyType,
add: if (XGetWindowProperty(dpy, window, _XA_WM_CLIENT_LEADER, 0, 4, False, AnyPropertyType,
context: PropGetClientLeader(Window window, Window *leader){    Atom type_ret;    int fmt_ret;    unsigned long nitems_ret;    unsigned long bytes_after_ret;    Window *win;    if (XGetWindowProperty(dpy, window, _XA_WM_CLIENT_LEADER, 0, 			   sizeof(Window), False, AnyPropertyType,			   &type_ret, &fmt_ret, &nitems_ret, &bytes_after_ret,			   (unsigned char**)&win)!=Success)      return 0;    if (!win) return 0;    *leader = (Window)*win;    XFree(win);    return 1;}