ve example, the output parameters will be the username and password.</p>

<p>If the username and password sent by the client were not valid, and error message is returned using <dfn>send_error_message()</dfn>.</p>

<p>If the operation was successful, the client will be sent back a response array containing the user's info.</p>


<h2>Formatting a Response</h2>

<p>Similar to <em>Requests</em>, <em>Responses</em> must be formatted as an array.  However, unlike requests, a response is an array
<strong>that con