title: How to use the optional hostname parameter in Node.js server.listen()
body: <p>From what I've read in tutorials so far, the optional <code>hostname</code> parameter to <code>server.listen(port[, hostname][, backlog][, callback])</code> has always been either <code>127.0.0.1</code> (loopback), <code>0.0.0.0</code> (<a href="https://stackoverflow.com/questions/20778771/what-is-the-difference-between-0-0-0-0-127-0-0-1-and-localhost">listen on every available network interface, the default option</a>), or one of the actual IP addresses available to the server. Everything else will give an <code>Error: listen EADDRNOTAVAIL</code>. Is that the whole picture? (I believe hostname is technically different from IP...)</p>
  
  <p>I wasn't able to find out too much about it from the <a href="https://nodejs.org/api/net.html#net_server_listen_port_hostname_backlog_callback" rel="noreferrer">doc</a>...</p>