Method 2 of traversing the tree

Non-recursive depth-first algorithm, implemented using a stack

define('DS', DIRECTORY_SEPARATOR);
function deep_first_list_files($from = '.')
{
 if(!is_dir($from)) {
 return false;
 }
 $ files = array();
 $dirs = array($from);
 while(NULL !== ($dir = array_pop($dirs))) {
 if( $dh = opendir($dir)) {
 while ( false !== ($file = readdir($dh))) {
 if($file == '.' || $file == '..') {
 continue;
 }
 $path = $dir . DS . $file;
 if(is_dir($path)) {
 $dirs[] = $path;
 } else {
 $files[] = $path;
 }
 }
 closedir($dh);
 }
 }
 return $files;
}
function profile($func, $trydir)
{
 $mem1 = memory_get_usage();
 echo '------------- ---------- Test run for '.$func.'() ';</li>
<li> flush();</li>
<li> $time_start = microtime(true);</li>
<li> $list = $func($trydir);</li>
<li> / /print_r($list);</li>
<li> $time = microtime(true) - $time_start;</li>
<li> echo 'Finished : '.count($list).' files';
 $mem2 = memory_get_peak_usage();
 printf ('Max memory for '.$func.'() : %0.2f kbytes Running time for '.$func.'() : %0.f s',
 ($mem2- $mem1)/1024.0, $time);
 return $list;
}
profile('deep_first_list_files', "D:wwwserver");
?>