+DEFUN ("x-focus-frame", Fx_focus_frame, Sx_focus_frame, 1, 1, 0,
+ doc: /* Set the input focus to FRAME.
+FRAME nil means use the selected frame.
+If there is no window system support, this function does nothing. */)
+ (Lisp_Object frame)
+{
+#ifdef HAVE_WINDOW_SYSTEM
+ x_focus_frame (decode_window_system_frame (frame));
+#endif
+ return Qnil;
+}