ULL</span>
<span class="fu"><a href="https://rdrr.io/r/base/print.html">print</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/names.html">names</a></span><span class="op">(</span><span class="va">x</span><span class="op">)</span><span class="op">)</span></code></pre></div>
<pre><code>NULL</code></pre>
</div>
<div id="reference-memory-mapped-data" class="section level2">
<h2 class="hasAnchor">
<a href="#reference-memory-mapped-data" class="anchor"></a>Reference memory-mapp