n class="n">system_dir</span><span class="p">(</span><span class="n">pattern</span><span class="o">=</span><span class="s1">&#39;*&#39;</span><span class="p">)</span><span class="w"></span>
<span class="w">          </span><span class="c">! select regular files and links</span>
<span class="w">          </span><span class="n">mymask</span><span class="o">=</span><span class="w"> </span><span class="n">isreg</span><span class="p">(</span><span class="n">filenames</span><span class="p">).</span><span class="n