ass="special">&amp;</span> <span class="identifier">ec</span><span class="special">,</span>       <span class="comment">// Result of operation</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">bytes_written</span>   <span class="comment">// Number of bytes written to the buffer sequence</span>
<span class="special">);</span>
</pre>
                    <p>
                      Regardless of whether the asynchronous op