session destroying

[tohan]

I have designed a web log in checking the username against a database and then storing the username in a session variable.

I start the login.php page with;
session_start();
session_register("sessionName"); //username

however this does not work the first time the user logs in and they have to log out via a logout.php page first where i have
session_destroy();

Then when they log in again all is okay and the session variables are registered

code from index.php to check session

session_start();
session_register("sessionName");
$sessionId=session_id();
//print("Session Id is: $sessionId");
//print("<br>Session Name is: $sessionName");
if(!$sessionName){

logout_User();

}

Any ideas why this is not working

using PHP4 on Windows NT4 and apache

[cheesehead]

If that is the whole code it does't look like you are actually setting the sessionName variable. The session_register only tells it that it is a session variable and doesn't actually populate it with anything. Add in a $sessionName = $username (or whatever the entered field is called).

As a note, I always find it better to pass in a different variable and then set the session variable to that.

e.g.
<!-- page1.php -->
....
<form action="page2.php">
<input type="text" name="username">
</form>
....

<!-- page2.php -->
....
session_register("sessionName");
$sessionName = $username;
....

Your session variable should be set after that.