3+ Character Domain Scanner

function get_rand_id($length)
{
  if($length>0) 
  { 
  $rand_id="";
   for($i=1; $i<=$length; $i++)
   {
   mt_srand((double)microtime() * 1000000);
   $num = mt_rand(1,36); // all characters
   //$num = mt_rand(26,36); only numbers
   //$num = mt_rand(1,26); only alphas
   $rand_id .= assign_rand_value($num);
   }
  }
return $rand_id;
}

<?php
$save = "domains.txt"; //where to save domains found
$amount = 100000; //amount of domains to scan for
for($i=0;$i < $amount;$i++){
    //you can edit this to scan for how many char the domain should have
    /* ex. 
        $name = get_rand_id(3); scans for 3 char domains
        $name = get_rand_id(4); scans for 4 char domains
        if you want to scan for more, then do this
            $ranlim = rand(3,5);
            if($ranlim == 3){
                $name = get_rand_id(3);
            }elseif($ranlim == 4){
                $name = get_rand_id(4);
            }elseif($ranlim == 5){
                $name = get_rand_id(5);
            }
    */
    $ranlim = rand(3,4);
    if($ranlim == 3){
        $name = get_rand_id(3);
    }elseif($ranlim == 4){
        $name = get_rand_id(4);
    }
    echo "Name: ".$name."\n";
    $content = getQuery($name);
    //echo $content;
    preg_match('#com: "(.*)", net: "(.*)", org: "(.*)"#', $content, $tld);
    $com = $tld[1];
    $net = $tld[2];
    $org = $tld[3];
    if($com == "a"){
        echo $name.".com is available.\n\n"; 
        $fh = fopen($save, 'a');
        fwrite($fh, $name.".com\n");
        fclose($fh);
    }elseif($com == "u"){
        echo $name.".com is unavailable.\n\n";
    }
    if($net == "a"){
        echo $name.".net is available.\n"; 
        $fh = fopen($save, 'a');
        fwrite($fh, $name.".net\n");
        fclose($fh);
    }elseif($net == "u"){
        echo $name.".net is unavailable.\n";
    }
    
    if($org == "a"){
        echo $name.".org is available.\n\n";
        $fh = fopen($save, 'a');
        fwrite($fh, $name.".org\n");
        fclose($fh);
    }elseif($org == "u"){
        echo $name.".org is unavailable.\n\n";
    }
}

function assign_rand_value($num)
{
  switch($num)
  {
    case "1":
     $rand_value = "a";
    break;
    case "2":
     $rand_value = "b";
    break;
    case "3":
     $rand_value = "c";
    break;
    case "4":
     $rand_value = "d";
    break;
    case "5":
     $rand_value = "e";
    break;
    case "6":
     $rand_value = "f";
    break;
    case "7":
     $rand_value = "g";
    break;
    case "8":
     $rand_value = "h";
    break;
    case "9":
     $rand_value = "i";
    break;
    case "10":
     $rand_value = "j";
    break;
    case "11":
     $rand_value = "k";
    break;
    case "12":
     $rand_value = "l";
    break;
    case "13":
     $rand_value = "m";
    break;
    case "14":
     $rand_value = "n";
    break;
    case "15":
     $rand_value = "o";
    break;
    case "16":
     $rand_value = "p";
    break;
    case "17":
     $rand_value = "q";
    break;
    case "18":
     $rand_value = "r";
    break;
    case "19":
     $rand_value = "s";
    break;
    case "20":
     $rand_value = "t";
    break;
    case "21":
     $rand_value = "u";
    break;
    case "22":
     $rand_value = "v";
    break;
    case "23":
     $rand_value = "w";
    break;
    case "24":
     $rand_value = "x";
    break;
    case "25":
     $rand_value = "y";
    break;
    case "26":
     $rand_value = "z";
    break;
    case "27":
     $rand_value = "0";
    break;
    case "28":
     $rand_value = "1";
    break;
    case "29":
     $rand_value = "2";
    break;
    case "30":
     $rand_value = "3";
    break;
    case "31":
     $rand_value = "4";
    break;
    case "32":
     $rand_value = "5";
    break;
    case "33":
     $rand_value = "6";
    break;
    case "34":
     $rand_value = "7";
    break;
    case "35":
     $rand_value = "8";
    break;
    case "36":
     $rand_value = "9";
    break;
  }
return $rand_value;
}

function get_rand_id($length)
{
  if($length>0) 
  { 
  $rand_id="";
   for($i=1; $i<=$length; $i++)
   {
   mt_srand((double)microtime() * 1000000);
   $num = mt_rand(1,36);
   $rand_id .= assign_rand_value($num);
   }
  }
return $rand_id;
}

function getQuery($name)
{
    $fp = fsockopen("www.bustaname.com", 80, $errno, $errstr, 30);
    fputs($fp, "GET /quick_check/".urlencode($name)." HTTP/1.1\r\n");
    fputs($fp, "Host: www.bustaname.com\r\n");
    fputs($fp, "User-agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.0.10) Gecko/2009042315 Firefox/3.0.10\r\n");
      fputs($fp, "Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8\r\n");
    fputs($fp, "Accept-Language: en-us,en;q=0.5\r\n");
    fputs($fp, "Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7\r\n");
    fputs($fp, "Connection: close\r\n\r\n");
    while (!feof($fp)) {
        $buf .= fgets($fp,128);
    }   
   fclose($fp);
   return $buf;
}
?>