session timeout

[chramya]

Hi,

Am new to PHP... I had created login form with session.. I wish to change my form as-"After idle time of 30 seconds session should expire and should go to login page once again"...

<?php
ini_set("session.gc_maxlifetime",30);
session_start();
if(session_is_registered('email'))
{
echo 'Login successful';
session_unset();
session_destroy();
}
else
{
header("location:main.html");
}
?>

I tried this code.... wat is the change that i have to do to achieve above said requirement...

Thanks,
Ramya

[PHP_Chimp]

the gc stands for garbage collection, so you could use this although you would need to set garbage collection to work on every request. This is not a good idea, as this will eat up a lot of php resource as it will preform garbage collection after each request. If you think about the number of requests that php gets thats a lot of additional garbage collection.

You could set something like -

$_SESSION['last_time'] = time();

Then on each request for a new page -

if ($_SESSION['last_time']+30 >= time() {
// last login + 30 seconds greater than present time
// kill session
}

<edit>
You need to be careful when killing sessions as sometimes session_unset doesnt actually work so well.

function kill_session() {
$_SESSION = array();
session_unset;
session_destroy();
}

This should get rid of all of the session as, you will reset the session to a blank array, then unset then destroy. This should remove all of the records, even those left on the server. There are a lot of user comments on the unset page about people having problems with sessions not getting unset.

[edited by: PHP_Chimp at 6:21 pm (utc) on Dec. 26, 2007]