AC_HEADER_TIME
AC_CHECK_HEADERS([X11/extensions/xf86vmode.h], [], [], [#include <X11/Xlib.h>])
AC_CHECK_HEADERS([X11/extensions/XI.h X11/extensions/XInput.h])
AC_HEADER_TIME
AC_CHECK_HEADERS([X11/extensions/xf86vmode.h], [], [], [#include <X11/Xlib.h>])
AC_CHECK_HEADERS([X11/extensions/XI.h X11/extensions/XInput.h])