function AuthenticateForm()
    {
        session_name();
        session_start();
        WriteHeaders("Authenticate");
        if ($_POST)
        {
            $error = LoginCheck($_POST);
            if (trim($error)=="")
            {
                $_SESSION['merchant_id'] = Login($_POST);
                if(isset($_SESSION['merchant_id']));
                {
                    echo "<form action = \"?\" method=\"post\">\n";
                    echo "Login Sucessful<br /><br />";
                    DisplayButton("submit","f_Main","Continue to Main Menu");

                    //test lines
                    echo "session is registered: ".session_is_registered("merchant_id");
                    echo "Merchant ID is : ".$_SESSION['merchant_id'];

                    echo "</form>";
                }
            }
            else
            {
                echo "Error : ".$error;
            }
        }
        WriteFooters();
    }
function Login ($forms)
    {
        $username = $forms['f_Username'];
        $password = $forms['f_Password'];

        /* do your sql query again, but now returning the id of member */
        OpenConnectionandDatabase($username,$password);

        $query = "SELECT * FROM Authenticate WHERE 'username' = \"".$username."\" AND 'password' = \"".$password."\"";
            echo $query;
        $result = mysql_query($query);
            echo $result;
        $row = mysql_fetch_array($result);
            echo "row value".$row['Merchant_ID'];
        $merchantid = $row['Merchant_ID'];
            echo $merchantid;

        CloseConnection();

        return $merchantid;
    }