How to run and read the results of command prompt/telnet from a processing sketch?

Processing Coding Questions
1

I’d like to run commands on cmd.exe from a processing sketch, reading the results. Is this possible, and is there a most simple example I can take a look at (such as executing dir and then reading the results to an array)?

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2

I’ve got this class Command from “Command.java”: :coffee:

And this test-drive “.pde” sketch: :racing_car:

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3

The command library seems like just what I was looking for, thanks. I’ll give it a try and come back with any questions or issues I have.

4 
import deadpixel.command.Command;

static final String BASH = platform == WINDOWS? "cmd /C " : "bash -c ";

static final String CD = "cd ";
static final String AMP = " && ", SPC = " ";

void setup() {
  Command cmd2 = new Command(BASH + "CD ../" + ENTER + "dir");
  //println(cmd2.command, ENTER); <-- this gives "cmd2.command" not visible error, both in the original unedited script and this stripped down one. Not sure what it is supposed to print.
  cmd2.run();
  //println("Success:", cmd.run(), ENTER);
  printArray(cmd2.getOutput());

  exit();
}

The output of this is:

“COMMAND ERROR: The system cannot find the path specified.”

If I just try running

Command cmd = new Command(BASH + “dir”);

It will printArray the results of the processing 3.5.3 directory.

How do I run a command, wait for a response, and then run another command? In my use case scenerio, I would need to wait for a server response, and depending on what the response is, enter another command. The server will reject the command if it isn’t in the same console session.

5

Which means does that server uses to communicate a response?
An exit ERRORLEVEL? Errorlevel - Windows CMD - SS64.com
Logs to STDERR? Command Redirection, Pipes - Windows CMD - SS64.com

Much probably you’re gonna need to write some “.bat” file in order to read the response and decide whether to issue another command while keeping the same session: If - Conditionally perform command - Windows CMD - SS64.com

I wonder if you should consider using some HTTP library instead?

6

I posted my attempt with sockets here, although I wasn’t able to get a connection to the server (in this case Google’s MX server on port 25).

I may have to look into executing telnet commands with a bat script, but I wish I could do it from within a processing sketch if possible.