ROS入门21讲笔记（三）代码形式写一个订阅者向发布者订阅消息

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catkin_create_pkg  receieve-turlepose roscpp rospy std_msgs geometry_msgs turtlesim

#include 
#include "turtlesim/Pose.h"

void postCallback(const turtlesim::Pose::ConstPtr &msg) //回调函数，参数是turtlesim::Pose::ConstPtr
{
	ROS_INFO("Turtle pose:x:%0.6, y:%0.6",msg->x,msg->y);//注意回调时间应该尽可能短
}

int main(int argc,char **argv)
{
	ros::init(argc,argv,"GetSubInfo");//初始化这个节点
	ros::NodeHandle n;				//订阅和发布都需要用到这个句柄
	
	ros::Subscriber getSub=n.subscribe("/turtle1/pose",10,postCallback);//最后一个参数是一个回调函数
	
	ros::spin();//循环等待方法，阻塞以查看队列是否有新消息进来，如果有就调用postCallback
	
	return 0;//因为前面在循环等待，所以一般不会执行到这一句
}