> > > The first error is still present for me, though: > > /home/bouffard/dev/ros/ros_flyer/flyer_controller/nodes/controller.cpp: > In member function ‘void > flyer_controller::Controller::controlModesStatusCallback(const > ros::MessageEvent flyer_controller::control_mode_status_ > >&)’: > /home/bouffard/dev/ros/ros_flyer/flyer_controller/nodes/controller.cpp:198: > error: invalid initialization of reference of type ‘const > flyer_controller::control_mode_statusPtr&’ from expression of type > ‘boost::shared_ptr flyer_controller::control_mode_status_ > >’ > The error is saying that you're initializing a reference to a pointer from a reference to a const pointer. It's an equivalent error to this: const char* foo = "hello"; char* bar = foo; blah.cpp:4: error: invalid conversion from ‘const char*’ to ‘char*’ In this case you need to be using: const flyer_controller::control_mode_status*Const*Ptr& msg = event.getMessage(); Josh