area privata con sessioni che da errori notice

[rocco.mod]

ho scaricato la classe e mi sembra valida , ma come devo fare per la connessione ?

session_set_save_handler (array(&$session, 'open'), 
                          array(&$session, 'close'), 
                          array(&$session, 'read'), 
                          array(&$session, 'write'), 
                          array(&$session, 'destroy'), 
                          array(&$session, 'gc')); 
class session{ 
    var $session_limit = 300; //life of sessions in seconds
    
    function session(&$db){
    //set db handler
    $this->db = $db;
    }
    /* Open session, if you have your own db connection 
       code, put it in here! */ 
    function open($path, $name) { 
        if (isset($this->db)) return TRUE; 
        else return FALSE;
    } 
    /* Close session */ 
    function close() { 
        /* This is used for a manual call of the 
           session gc function */ 
        $this->gc(0); 
        return TRUE; 
    } 
    /* Read session data from database */ 
    function read($ses_id) {
        $session_sql = "SELECT * FROM sessions WHERE ses_id = '$ses_id'"; 
        $session_res = $this->db->getRow($session_sql); 
        if (!$session_res) { 
            return ''; 
        } 
       if ($session_res) { 
            $ses_data = $session_res["ses_value"];
        return $ses_data; 
        } else { 
            return ''; 
        } 
    } 
    /* Write new data to database */ 
    function write($ses_id, $data) { 
        $session_sql = "UPDATE sessions SET ses_time='" . time() 
                     . "', ses_value='$data' WHERE ses_id='$ses_id'"; 
        $session_res = $this->db->query($session_sql); 
        if (!$session_res) { 
            return FALSE; 
        } 
        if ($this->db->affectedRows() > 0) { 
            return TRUE; 
        } 
        $session_sql = "INSERT INTO sessions (ses_id, ses_time, ses_start, ses_value)" 
                     . " VALUES ('$ses_id', '" . time() 
                     . "', '" . time() . "', '$data')"; 
        $session_res = $this->db->query($session_sql); 
        if (!$session_res) {     
            return FALSE; 
        }         else { 
            return TRUE; 
        } 
    } 
    /* Destroy session record in database */ 
    function destroy($ses_id) { 
        $session_sql = "DELETE FROM sessions WHERE ses_id = '$ses_id'"; 
        $session_res = $this->db->query($session_sql); 
        if (!$session_res) { 
            return FALSE; 
        }         else { 
            return TRUE; 
        } 
    } 

    // Garbage collection removes old sessions 
    function gc($life) { 
        $ses_life = time() - $this->session_limit; 
        $session_sql = "DELETE FROM sessions WHERE ses_time < $ses_life"; 
        $session_res = $this->db->query($session_sql); 
        if (!$session_res) { 
            return FALSE; 
        }         else { 
            return TRUE; 
        } 
    } 
        // Users online 
    function users() { 
        $users_sql = "SELECT COUNT(ses_id) FROM sessions"; 
        $users_res = $this->db->getOne($users_sql); 
        if (!$users_res) { 
            return NULL; 
        }         else { 
            return $users_res; 
        } 
    } 
} 

io uso la connessione cosi:

class DB{
var $db_host ='localhost';
var $db_user ='root';
var $db_pass ='maurizio';
var $db_name ='diva';


var $SMARTY_LIBRARY ='';



    //PHP5 Constructor
    function __construct() {
        global $db_host,$db_user,$db_pass,$db_name;
            
        $this->host = $db_host;
        $this->user = $db_user;
        $this->pass = $db_pass;
        $this->name = $db_name;
    }
    //PHP4 Constructor
    function database() {
        global $db_host,$db_user,$db_pass,$db_name;
        
        $this->host = $db_host;
        $this->user = $db_user;
        $this->pass = $db_pass;
        $this->name = $db_name;
    }

 function connect()
 {
   @mysql_connect($this->db_host,$this->db_user,$this->db_pass)or die("non riesco a connettermi".mysql_error());
  @mysql_select_db($this->db_name)or die("non riesco selezionare il database");
 }

 function disconnect()
 {
  if( !mysql_close()){
  die("Could not close DB");
  }
 }
}