a callback function to be called on success, failure or timeout (only if ERR_INPROGRESS is returned!) </td></tr>
    <tr><td class="paramname">callback_arg</td><td>argument to pass to the callback function </td></tr>
  </table>
  </dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>a err_t return code. </dd></dl>

</div>
</div>
<a id="gae84449f60dca6b863142daca8e03ce79"></a>
<h2 class="memtitle"><span class="permalink"><a href="#gae84449f60dca6b863142daca8e03ce79">&#9670;&nbsp;</a></span>dns_gethostby