n class="special">;</span>
  <span class="identifier">size_t</span> <a class="link" href="buffer_iterator.html#idm45152240004800-bb"><span class="identifier">get_index</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
  <span class="identifier">T</span> <a class="link" href="buffer_iterator.html#idm45152240003680-bb"><span class="identifier">read</span></a><span class="special">(</span><span class="identifier">command_queu