etadata.  Raise UnknownFormatError when the file format is unknown.</p>
<p>Open the file and loop through the readers until one returns some results.</p>


</dd>
<a id="keyName,string,string,string"></a>
<dt><pre><span class="Keyword">proc</span> <span class="Identifier">keyName</span><span class="Operator">*</span><span class="Other">(</span><span class="Identifier">readerName</span><span class="Other">:</span> <span class="Identifier">string</span><span class="Other">;</span> <span class="Identifier">sect