&gt; int -&gt; <a href="Digest.html#TYPEt">t</a></code></pre><div class="info ">
<div class="info-desc">
<p>If <code class="code">len</code> is nonnegative, <code class="code"><span class="constructor">Digest</span>.channel&nbsp;ic&nbsp;len</code> reads <code class="code">len</code>
   characters from channel <code class="code">ic</code> and returns their digest, or raises
   <code class="code"><span class="constructor">End_of_file</span></code> if end-of-file is reached before <code class="code">len</code>