Can someone help comment this 60 line script, so I can learn :)

I am trying to learn some php and wanted to start understanding this script: http://www.sandaru1.com/2007/07/04/how-to-find-free-mp3-using-google/

   1. <?  
   2.     $stderr = fopen('php://stderr', 'w');  
   3.     set_time_limit(0);  
   4.     error_reporting(0);  
   5.   
   6.     $urls[] = "http://www.mcgees.org/mp3/pearl_jam/";  
   7.     $urls[] = "http://www.xieish.net/Collective%20Soul/";  
   8.     $urls[] = "http://www.asilentflute.com/mp3/";  
   9.     $urls[] = "http://www.semret.org/music/";  
  10.     $urls[] = "http://www.koreangirlssuck.com/emotion/mp3/";  
  11.     $urls[] = "http://www.vrees.net/mp3/";  
  12.     $urls[] = "http://www.webpiri.net/Mp3/";  
  13.     $urls[] = "http://pierre33200.free.fr/Music/";  
  14.   
  15.     $done = array();  
  16.   
  17.     for($i=0;$i<count($urls);$i++) {  
  18.         $url = $urls[$i];  
  19.         $done[strtolower($url)] = true;  
  20.         $temp = parse_url($url);  
  21.         $path = pathinfo($temp['path']);  
  22.         $domain = $temp['host'];  
  23.   
  24.         if ($path['extension']!="") {  
  25.             if (strtolower($path['extension'])=="mp3"  
  26.                 || strtolower($path['extension'])=="wma") {  
  27.                 echo $url."n";  
  28.                 continue;  
  29.             } else {  
  30.                 fwrite($stderr,"Escaping $url : Not mp3n");  
  31.                 continue;  
  32.             }  
  33.         }  
  34.   
  35.         fwrite($stderr,"Proccessing $urln");  
  36.   
  37.         $html = file_get_contents($url);  
  38.   
  39.         $direct = preg_match("/index of/i",$html);  
  40.         if ($direct==false) {  
  41.             fwrite($stderr,"Error : Not a directy indexn");  
  42.             continue;  
  43.         }  
  44.   
  45.         $count = preg_match_all("/<a href="(.*?)">.*?</a>/i",  
  46.                 $html,$matches);  
  47.         foreach ($matches[1] as $match) {  
  48.             // Ignore the pages link to same url  
  49.             if ($match[0] == "?")  
  50.                 continue;  
  51.             if (substr($match,0,7)=="http://")  
  52.                 $cur = $match;  
  53.             else if ($match[0] == "/")  
  54.                 $cur = "http://".$domain.$match;  
  55.             else  
  56.                 $cur = $url.$match;  
  57.             if (!isset($done[strtolower($cur)]))  
  58.                 $urls[]=$cur;  
  59.         }  
  60.     }  
  61.     fclose($stderr);  
  62. ?>  

PHP:

Thanks for your time!

 

There are syntax errors in the script... are you sure it does even work?

And do you have ANY knowledge about PHP? Because commenting won't help much if you have no idea at all. And commenting 60 lines just for fun is nothing I'm too interested in, to be honest.

Or are there just a few specific parts that you need help with?