We can achieve HelloWorld Program, for example , Brief introduction ROS How to use , The general flow is as follows ：

1. Create a workspace and initialize ;
2. Create Feature Pack ;
3. Edit source file ;
4. Edit profile ;
5. Compile and execute .

1 Create a workspace and initialize

 First, you need to open the terminal , Enter the following command ：
	mkdir -p  Custom workspace name /src
	cd  Custom workspace name 
	catkin_make

The above order , First, a workspace and a src subdirectories , Then enter the workspace and call catkin_make Command compilation .

2 Get into src establish ros Package and add dependencies

 cd src
 catkin_create_pkg  Customize ROS Package name  roscpp rospy std_msgs

The above order , The next workspace name will be generated “ Customize ROS Package name ” Function pack , The Feature Pack depends on roscpp、rospy And std_msgs, among roscpp It's using C++ Implementation of the library , and rospy Is the use python Implementation of the library ,std_msgs It's a standard message library , establish ROS Function pack time , Generally, we will rely on these three libraries to realize .

3 Get into ros Bag src Directory edit source file

cd  Self defined ROS package 

newly build C++ File and write execution code ( File name customization )：

#include "ros/ros.h"

int main(int argc, char *argv[])
{
    
    // perform  ros  Node initialization 
    ros::init(argc,argv,"hello");
    // establish  ros  inode handle ( Not necessary )
    ros::NodeHandle n;
    // Console output  hello world
    ROS_INFO("hello world!");

    return 0;
}

4 edit ros The configuration file under the package : Cmakelist.txt file

 take 136 Yes add_executable and 149 Yes target_link_libraries Change the code to ：
	add_executable( step 3 The source file name of  src/ step 3 The source file name of .cpp)
	target_link_libraries( step 3 The source file name of  ${catkin_LIBRARIES})

5 Enter the workspace directory and compile

cd  Custom workspace name 
catkin_make

Generate build devel …

6 perform

 Open the terminal 1 perform ：
	roscore
 Open the terminal 2 perform ：
	cd  working space 
	source ./devel/setup.bash
	rosrun  Package name  C++ node 

Command line output : HelloWorld!