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Running 2 nodes in a single docker container [community-contributed]

Pull the ROS docker image with tag “eloquent-desktop”.

docker pull osrf/ros:eloquent-desktop

Run the image in a container in interactive mode.

$ docker run -it osrf/ros:eloquent-desktop
root@<container-id>:/#

Your best friend is the ros2 command line help now.

root@<container-id>:/# ros2 --help

E.g. list all installed packages.

root@<container-id>:/# ros2 pkg list
(you will see a list of packages)

E.g. list all executables:

root@<container-id>:/# ros2 pkg executables
(you will see a list of <package> <executable>)

Run a minimal example of 2 C++ nodes (1 topic subscriber listener, 1 topic publisher talker) from the package demo_nodes_cpp in this container:

ros2 run demo_nodes_cpp listener &
ros2 run demo_nodes_cpp talker