Session (Logged In) Should be easy

[akrocks_extreme]

Ok, i'm using session to keep the user logged in.

<?
session_start();

//blah blah blah

if ($_SESSION['is_login'] != 'yes')
{
include 'login.php';
}
else
{
//blah blah blah
}

?>

but i get an error Notice: Undefined index: is_login in blah..
see, if i set it to $_SESSION['is_login'] = 'no'; each time the person goes to index.php then it will log them out... so how do i advoid the error without logging out the user? btw, this only happens of coruse until the user logs in. thanks for your help in advanced.

[Kudose]

Should go something like this:

<?
session_start();

if(isset($_POST['form'])){
$username = $_POST['username'];
$password = $_POST['password'];

//check if user and pass are in DB
if(!$username || !$password){
//if not in db kill here
echo "Error!"; exit(); } else {
//if user and pass are correct set session value
$_SESSION['[e-mail]'] = $username;
//do whatever here...
include('secure.php');
echo "Hello, $_SESSION['[e-mail]']";
}} else {
//form
}
?>

[Kudose]

or you could do:

if($_SESSION['is_login'] !== FALSE){
//do stuff
} else {
//kill stuff
}

[akrocks_extreme]

but thats not my problem... I'm 'if'ing before $_SESSION['is_login'] is set.... thats why i'm getting the error... how can i set is_login only once or, even better, if not set then set it as false?

-edit-
you know what? its working now.. i figured out my problem.. i set up a server on my machine and my php.ini file wasnt set up correctly, but now it is and everything seems to be working now!