 stream layers. In this case it will be the tcp_stream.</span>
        <span class="comment">// This timeout will apply to all subsequent operations collectively.</span>
        <span class="comment">// That is to say, they must all complete within the same 30 second</span>
        <span class="comment">// window.</span>

        <span class="identifier">get_lowest_layer</span><span class="special">(</span><span class="identifier">stream</span><span class="special">).</span><span class="identifier">expires_