php session unset do not work sometimes

Question

I have this code to change session name:

 session_name(md5('seg'.$_SERVER['REMOTE_ADDR'].$_SERVER['HTTP_USER_AGENT']));

and this to logout:

session_name(md5('seg'.$_SERVER['REMOTE_ADDR'].$_SERVER['HTTP_USER_AGENT']));
session_start();

$user = $_SESSION["user"];

unset($_SESSION['id']);
unset($_SESSION['user']);

session_destroy();

the problem is that sometimes it works, in first time. sometimes I need to click to logout about 3 times. What may cause this?

Answer 1

Try to set whole session to empty array:

session_start();
$_SESSION = array();
session_destroy();

// $_SESSION is still accessible till page change.