alibizhan / publishersubscriberroskinetic

Publisher and Subscriber (C++) Ros Kinetic

Publisher and Subscriber (C++) Ros Kinetic

Making a workspace

$ mkdir -p ~/catkin_ws/src
$ cd ~/catkin_ws/
$ catkin_make

catkin_make, Creates CmakeLists.txt file inside src folder

now we go to $ cd ~/catkin_ws/src and create the beginner_tutorials package
$ catkin_create_pkg beginner_tutorials std_msgs rospy roscpp

It creates the beginner_tutorials folder and it has a package.xml and a CmakeLists.tx in it.
Now open the package.xml file and if the package format is "2" then package format = "2" if there is <run_depend> tag, we need to replace it with <exec_depend> because <run_depend> belongs to old version.

Now we write a publisher talker node:

$ roscd beginner_tutorials
$ mkdir -p src

We create the src/talker.cpp file in the beginner_tutorials directory and put the publisher's c++ codes in it. We follow the same steps for the subscriber.

Create msg:

$ roscd beginner_tutorials
$ mkdir msg
$ echo "int64 num" > msg/Num.msg

Create srv:

$ roscd beginner_tutorials
$ mkdir srv
$ roscp rospy_tutorials AddTwoInts.srv srv/AddTwoInts.srv

Then we add the following lines in package.xml and CmakeLists.txt file.

generate_messages(DEPENDENCIES std_msgs)

findg_package(catkin REQUIRED COMPONENTS
roscpp
rospy
std_msgs
message_generation
genmsg )

In your catkin workspace run the following commands

$ roscd beginner_tutorials
$ cd ../..
$ catkin_make install
$ cd -

Publisher:

$ roscore

In your catkin workspace

$ cd ~/catkin_ws
$ source ./devel/setup.bash
$ rosrun beginner_tutorials talker

Subscriber:

$ roscore

In your catkin workspace

$ cd ~/catkin_ws
$ source ./devel/setup.bash
$ rosrun beginner_tutorials listener