Logout with using session

[dr.4030]

i used session in my admin panel so when i click on log out button in server i faced with this msgs

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /home/royalfa/public_html/admin/logout.php:2) in /home/royalfa/public_html/admin/logout.php on line 5

Warning: Cannot modify header information - headers already sent by (output started at /home/royalfa/public_html/admin/logout.php:2) in /home/royalfa/public_html/admin/logout.php on line 7

and here it is my php commands :

<title>Logout</title>
<?php
//error_reporting(0);
ob_start();
session_start();
unset($_SESSION);
session_destroy();
header("location:index.php");
ob_end_flush();
?>

any body help me ?????

[pritaeas]

Remove everything before <?php . You will not see the title anyway, because the page is redirected.

[dr.4030]

Thanks my friend