(PHP 4, PHP 5, PHP 7)
closedir — Close directory handle
$dir_handle
  ] )
   Closes the directory stream indicated by
   dir_handle. The stream must have previously
   been opened by opendir().
  
Example #1 closedir() example
<?php
$dir = "/etc/php5/";
// Open a known directory, read directory into variable and then close
if (is_dir($dir)) {
    if ($dh = opendir($dir)) {
        $directory = readdir($dh);
        closedir($dh);
    }
}
?>