Using the function

To make everything fit together the complete function is:

function validateEmail($email){
 list($name,$Domain) = split('@',$email);
 $result=getmxrr($Domain,$POFFS);
 if(!$result){$POFFS[0]=$Domain;}
 $timeout=5;
 $oldErrorLevel=
             error_reporting(!E_WARNING);
 $result=false;
 foreach($POFFS as $PO )
 {
  $sock = fsockopen($PO, 25, 
           $errno, $errstr,  $timeout);
  if($sock){
   fwrite($sock, "HELO Mydomain.com\n");
   $response= getResponse($sock);
   fwrite($sock,
     "MAIL FROM: <me@mydomain.com>\n");
   $response= getResponse($sock);
   fwrite($sock,"RCPT TO: <".$email.">\n");
   $response= getResponse($sock);
   list($code,$msg)=explode(' ',$response);
   fwrite($sock,"RSET\n");
   $response= getResponse($sock);
   fwrite($sock,"quit\n");
   fclose($sock);
   if ($code == '250') {
    $result= true;
    break;
   }
  }
 }
 error_reporting($oldErrorLevel);
 return $result;
}

To use the function you simply write something like:

if( validateEmail("name@domain")){
 echo "valid";
}else{
 echo "not valid";
}

There is a small possibility that if you use this sort of validation too often at any given site then you might be blacklisted, but as long as the frequency is low enough not to annoy it should be fine.

To access the code for this project, once you have registered,  click on CodeBin.

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