Question

Say we have this method to make an ssh to another machine. How would I get the output from that machines terminals back to the host machine

  public void getSSHreply()
  {
    Process p;

    // Set up the arguments for ProcessBuilder
    String[] cmd = 
    {
        "/usr/bin/ssh", 
        "someRemoteMachine", //This machine will authenticate with keys, hence no pw needed
        "./myprog",
    };

    try
    {
            p = Runtime.getRuntime().exec(cmd);

            //How would I redirect stdout back to host machine?
            StringBuffer s = new StringBuffer();
            BufferedReader input = new BufferedReader(new InputStreamReader(p.getInputStream()));

            while (input.readLine() != null) 
            {
                 s.append(input.readLine() + "\n");
            }

            System.out.println(s.toString());


    }
    catch (IOException e)
    {
            System.err.println("Failed to read & or start ");
    }

  }

Answer 1

The Process object has methods for getting the STDOUT, STDERR, and STDIN streams. (ex. getOutputStream()).

You may want to look into commons-exec for more convenient ways to launch and manager external programs, which has tools like StreamPumper to redirect data.