In the composition case none of the nodes is in charge of the main function / main thread. Therefore you either have to use a timer to get notified in regular intervals or start your own thread (with all the implications for locking / thread safety). --- [Visit Topic](https://discourse.ros.org/t/ros2-composition/2469/2) or reply to this email to respond. If you do not want to receive messages from ros-users please use the unsubscribe link below. If you use the one above, you will stop all of ros-users from receiving updates. ______________________________________________________________________________ ros-users mailing list ros-users@lists.ros.org http://lists.ros.org/mailman/listinfo/ros-users Unsubscribe: