title: listen tcp 127.0.4.1:2040: bind: can't assign requested address
body: <p>I am using this golang code:</p>
  
  <pre><code>l, err := net.Listen("tcp", "127.0.4.1:2040")
  
  if err != nil {
      log.Fatal("d0b9184a-5248-413e-a5a8-30fea66997f5:", err)
  }
  
  log.Fatal(s.Serve(l))
  </code></pre>
  
  <p>I am getting this error:</p>
  
  <blockquote>
    <p>listen tcp 127.0.4.1:2040: bind: can't assign requested address</p>
  </blockquote>
  
  <p>anyone know why that won't work?</p>