Subscribe /tilt_controller1/state to know current position

edit

Hi people,

I am working with Dynamixel Servomotor AX-12+ in ROS fuerte and I need to know its current position.

In my code I subscribe to /tilt_controller1/state this is the info topic:

youbot@diego-VPCEH2K1E:~$ rostopic info /tilt_controller1/state
Type: dynamixel_msgs/JointState

but I dont know how to put the arguments of the callback, this is my code:

#include <dynamixel_msgs/JointState.h>
//----------------
void callback(const dynamixel_msgs::JointState& str)
{
    //str.current_pos
    std::cout<<"rotacion"<<std::endl;
}
//-------
sub = n.subscribe("/tilt_controller1/state", 1, callback);

The error is:

fatal error: dynamixel_msgs/JointState.h: No such file or directory

I think is a mistake with the library...is the rest of the code ok? Please can somebody help me?

Thanks