ade up of
    format tokens. Some of the tokens need an additional prefix. Possible
    prefixes are <code>c</code> for "client", <code>s</code> for "server",
    <code>cs</code> for "client to server", <code>sc</code> for
    "server to client" or <code>x</code> for "application specific".
    Furthermore some tokens are completed by an additional selector.
    See the <a href="http://www.w3.org/TR/WD-logfile.html">W3C specification</a>
    for more information about the format.</p>

    <p>The following f