WebSocket
                      frames. The implementation will copy the caller provided data
                      before the function returns.
                    </p>
                  </td>
</tr>
<tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="identifier">handler</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      The completion handler to invoke when the operation completes.
                 