title: TFTP C++ not receiving ACK
body: <p>I am writing a TFTP Client using C++. I was able to send a read request using "octet" mode to a default TFTP Client (tftpd32). The problem is that I am unable to send the ACK back at the regular TFTP respond. I am getting the following error: </p>
  
  <pre><code>Connection received from 127.0.0.1 on port 51401 [27/07 23:03:15.612]
  Read request for file &lt;test.txt&gt;. Mode octet [27/07 23:03:15.612]
  Using local port 51402 [27/07 23:03:15.612]
  Connection received from 127.0.0.1 on port 51401 [27/07 23:03:18.624]
  Unexpected request 4 from peer [27/07 23:03:18.624]
  Returning EBADOP to Peer [27/07 23:03:18.624]
  </code></pre>
  
  <p>Why I am able to send the RRQ but not the ACK using the same method?</p>