sql server - is there any func to set extension=php_mssql.dll without editing in php.ini using functions like we used ini_set(); method

  $con=mysql_connect('$url','$dbuser','$dbpass');

  if(!$con){
  die('cannot establish connection:'.mysql_error());
}
 $db=mysql_select_db("$db");
 if(!$db){
die('cannot found database:'.mysql_error());

 }
 ?>

Giving warnings :-

Warning: mysql_connect(): php_network_getaddresses: getaddrinfo
failed: No such host is known. in D:\xampp\htdocs\connection.php on
line 3

Warning: mysql_connect(): php_network_getaddresses: getaddrinfo
failed: No such host is known. in D:\xampp\htdocs\connection.php on
line 3 cannot establish connection:php_network_getaddresses:
getaddrinfo failed: No such host is known.

Can anyone help ?