pan class="lineno">   23</span>&#160;<span class="preprocessor">#pragma once</span></div><div class="line"><a name="l00024"></a><span class="lineno">   24</span>&#160;</div><div class="line"><a name="l00025"></a><span class="lineno">   25</span>&#160;<span class="preprocessor">#include &lt;atomic&gt;</span></div><div class="line"><a name="l00026"></a><span class="lineno">   26</span>&#160;<span class="preprocessor">#include &lt;condition_variable&gt;</span></div><div class="line"><a name="l00027"></a><span 