function login ($action,$user = '',$pass = '') {
        session_start();
        if ($action == 'check') {
            if($_SESSION['logged'] && ($_SESSION['key'] == 'AkerTech_'.md5($_SESSION['user']))) {
                return true;
            } else {
                include('fLogin.php');
                die();
              }
        }
        else if ($action == 'enter') {
            $pass = md5($pass);
            $row = consult("SELECT * FROM users WHERE user = '$user' AND password = '$pass'");
            if ($row != 0) {
                $_SESSION['logged'] = true;
                $_SESSION['uid'] = $row[0]->id;
                $_SESSION['user'] = $row[0]->user;
                $_SESSION['key'] = 'AkerTech_'.md5($row[0]->user);
                return true;
            } else {
                echo "<script>alert('error')</script>";
            }
        }
}