ros topic listener

#include<ros/ros.h>
#include<std_msgs/String.h>
#include<ros_fb/message.h>
void chatterCallback(const ros_fb::message::ConstPtr& msg)
{
    ROS_INFO("I heard %d",msg->trueorfalse);
}
int main(int argc, char *argv[])
{
    ros::init(argc, argv, "listener");
    ros::NodeHandle nh;
    ros::Subscriber sub=nh.subscribe("message_info",1,chatterCallback);
    ros::spin();
    return 0;
}