pan class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">buffer_copy</span><span class="special">(</span>
    <span class="keyword">const</span> <span class="identifier">MutableBufferSequence</span> <span class="special">&amp;</span> <span class="identifier">target</span><span class="special">,</span>
    <span class="keyword">const</span> <span class="identifier">ConstBufferSequence</span> <span class="special">&amp;</span> <span class=