class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">Handler</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">async_sendfile</span><span class="special">(</span><span class="identifier">tcp</span><span class="special">::</span><span class="identifier">socket</span><span class="special">&amp;</span> <span class="identifier">sock</span><span class="special">,</span> <span class="keyword