How to execute bash command in Node.js and get exit code?

To execute bash command in Node.js and get exit code, we call exec.

For instance, we write

const dir = exec("ls -la", (err, stdout, stderr) => {
  console.log(stdout);
});

dir.on("exit", (code) => {
  console.log(code);
});

to call exec to run the ls -la command.

We get the output from stdout in the callback.

Then we call dir.on to listen for the exit event.

And we get the exit code from code in the callback.