How to check if global ROS node is already running in MATLAB?

Hi, I am using Robotics Toolbox to interface MATLAB and ROS. Before doing rosinit('http://192.68.0.43:11311') i want to check whether a Global Ros Node corresponding to it is running. What are the steps to accomplish that?

Answer 1

[Marcelino Almeida]

I know it has been a long time, but I decided to post an answer here in case other people might be wondering how to do this.

Although there isn't much documentation on this, and this might not exist in future versions of the Robotics Toolbox, I've been able to check for node running through the following call:

robotics.ros.internal.Global.isNodeActive

The command above returns 1 if active, 0 if inactive.

[Alen Alempijevic]

This is a great hack, but access to the variable robotics.ros.internal.Global seems to be removed in 2019b. You can wrap the command in a try catch

      try
        rosinit
      catch ME
          fprintf(2,'%s\n',ME.message);
      end

[Thomas Stubbs]

I was able to do the Marcelino's solution in 2022b with a slight change:

ros.internal.Global.isNodeActive