Create an EMC error at start of motion when there is no realtime

Author: hdiethelm

src/emc/motion/motion.c

@@ -413,6 +413,14 @@ int rtapi_app_main(void)
 
     old_handler = rtapi_get_msg_handler();
     rtapi_set_msg_handler(emc_message_handler);
+
+    //Warn user if no realtime is available
+    //This has to be done after rtapi_set_msg_handler() so
+    //it propagates to all GUI's that handle motion errors
+    if(rtapi_is_realtime() == 0) {
+        rtapi_print_msg(RTAPI_MSG_ERR, "MOTION: no realtime detected.\n");
+    }
+
     return 0;
 }