Help modify to use PEAR

[mrbaseball34]

I have some code to validate email addresses.
However, the getmxrr and checkdnsrr functions
are not supported on Windows and the documentation
says that I must use the PEAR Net_DNS library.

I know nothing about using PEAR and would like some
help in understanding how to convert this code to use PEAR.

function validateEmail ($email) 
{ 
    global $SERVER_NAME; 
    $return = array (false, ""); 
    list ($user, $domain)  = split ("@", $email, 2); 
    $arr = explode (".", $domain); 
    $count = count ($arr); 

if (($count>  2) and ($arr[$count - 2]=='com' or $arr[$count - 2]=='org' or $arr[$count - 2]=='net' or $arr[$count - 2]=='edu' or $arr[$count - 2]=='mil' or $arr[$count - 2]=='k12')) 
{ 
       $tld = $arr[$count - 3].".".$arr[$count - 2] . "." . $arr[$count - 1]; 

} else { 
       $tld = $arr[$count - 2] . "." . $arr[$count - 1]; 
} 

if (checkdnsrr ($tld, "MX")) 
   { 
    if (getmxrr ($tld, $mxhosts, $weight)) 
       { 
         for ($i = 0; $i < count ($mxhosts); $i++) 
             { 
               $fp = fsockopen ($mxhosts[$i], 25); 
           if ($fp) 
                  { 
               $s = 0; 
               $c = 0; 
               $out = ""; 
               set_socket_blocking ($fp, false); 
                   do 
                       { 
                    $out = fgets ($fp, 2500); 
                    if (ereg ("^220", $out)) { 
                         $s = 0; 
                         $out = ""; 
                         $c++; 
                          } else if (($c > 0) && ($out == "")) { 
                                    break; 
                       } else { 
                         $s++; 
                             } 
                    if ($s == 9999) 
                                { 
                              break; 
                        } 
               } while ($out == ""); 
             set_socket_blocking ($fp, true);                           

                     fputs ($fp, "HELO $SERVER_NAME\n"); 
                 $output = fgets ($fp, 2000); 
             fputs ($fp, "MAIL FROM: <info@" . $tld . ">\n"); 
             $output = fgets ($fp, 2000); 
             fputs ($fp, "RCPT TO: <$email>\n"); 
             $output = fgets ($fp, 2000); 
             if (ereg ("^250", $output)) 
                     { 
                  $return[0] = true; 
             } else { 
                  $return[0] = false; 
                  $return[1] = $output; 
             } 
             fputs ($fp, "QUIT\n"); 
             fclose($fp); 
                 if ($return[0] == true) { 
                   break; 
             } 
            } 
      } 
   } 
} 
return $return; 
}

[mrbaseball34]

I found the answers on php.net in the user comments for
checkdnsrr and getmxrr.

function getmxrr($hostname, &$mxhosts)
{
   $mxhosts = array();
   exec('nslookup -type=mx '.$hostname, $result_arr);
   foreach($result_arr as $line) 
   {
     if (preg_match("/.*mail exchanger = (.*)/", $line, $matches)) 
         $mxhosts[] = $matches[1];
   }
   return( count($mxhosts) > 0 );
}//--End of workaround

function checkdnsrr($hostName, $recType = '') 
{ 
 if(!empty($hostName)) { 
   if( $recType == '' ) $recType = "MX"; 
   exec("nslookup -type=$recType $hostName", $result); 
   // check each line to find the one that starts with the host 
   // name. If it exists then the function succeeded. 
   foreach ($result as $line) { 
     if(eregi("^$hostName",$line)) { 
       return true; 
     } 
   } 
   // otherwise there was no mail handler for the domain 
   return false; 
 } 
 return false; 
} 

function validateEmail ($email) 
{ 
    global $SERVER_NAME; 
    $return = array (false, ""); 
    list ($user, $domain)  = split ("@", $email, 2); 
    $arr = explode (".", $domain); 
    $count = count ($arr); 

if (($count>  2) and ($arr[$count - 2]=='com' or $arr[$count - 2]=='org' or $arr[$count - 2]=='net' or 
    $arr[$count - 2]=='edu' or $arr[$count - 2]=='mil' or $arr[$count - 2]=='k12')) 
{ 
   $tld = $arr[$count - 3].".".$arr[$count - 2] . "." . $arr[$count - 1]; 

} else { 
   $tld = $arr[$count - 2] . "." . $arr[$count - 1]; 
} 

if checkdnsrr($tld, 'MX') {
{ 
if (getmxrr ($tld, $mxhosts)) 
   { 
     for ($i = 0; $i < count ($mxhosts); $i++) 
         { 
           $fp = fsockopen ($mxhosts[$i], 25); 
       if ($fp) 
              { 
           $s = 0; 
           $c = 0; 
           $out = ""; 
           set_socket_blocking ($fp, false); 
               do 
                   { 
                $out = fgets ($fp, 2500); 
                if (ereg ("^220", $out)) { 
                     $s = 0; 
                     $out = ""; 
                     $c++; 
                      } else if (($c > 0) && ($out == "")) { 
                                break; 
                   } else { 
                     $s++; 
                         } 
                if ($s == 9999) 
                            { 
                          break; 
                    } 
           } while ($out == ""); 
         set_socket_blocking ($fp, true);                           
                 fputs ($fp, "HELO $SERVER_NAME\n"); 
             $output = fgets ($fp, 2000); 
         fputs ($fp, "MAIL FROM: <info@" . $tld . ">\n"); 
         $output = fgets ($fp, 2000); 
         fputs ($fp, "RCPT TO: <$email>\n"); 
         $output = fgets ($fp, 2000); 
         if (ereg ("^250", $output)) 
                 { 
              $return[0] = true; 
         } else { 
              $return[0] = false; 
              $return[1] = $output; 
         } 
         fputs ($fp, "QUIT\n"); 
         fclose($fp); 
             if ($return[0] == true) { 
               break; 
         } 
        } 
  } 
   } 
} 
return $return; 
}