title: How to invoke external command from within Kotlin code?
body: <p>I want to invoke an external command from Kotlin code.</p>
  <ul>
  <li>In C/Perl, I would use the <code>system()</code> function.</li>
  <li>In Python, I would use the subprocess module.</li>
  <li>In Go, I would use os/exec, and etc.</li>
  </ul>
  <p>But how do I do this in Kotlin?</p>