variable problems

LordRogaine

I'm registering variables in sessions and using them throughout my site. I have tested some new changes that I have made and everything works perfectly. For most of the people on my site it works perfectly also, but for some reason there is a small percentage os users where the variables are not registering properly for some strange reason. This is the setup I am using--

<?
session_start();

if (empty($_SESSION['username'])){

   header ("location:logout.htm");

   exit();
}

if (empty($_SESSION['userid'])){

   header ("location:logout.htm");

   exit();
}

For some reason these variables which I have always passed from page to page are suddenly not registering for certain people and they are therefore being logged out of my site. One user told me he is using a
Macintosh Powerbook with Safari browser. Would this have an effect on the variables at all?

zabmilenko

http://us2.php.net/header

Says the following:

Note: HTTP/1.1 requires an absolute URI as argument to Location: including the scheme, hostname and absolute path, but some clients accept relative URIs. You can usually use $SERVER['HTTP_HOST'], $SERVER['PHP_SELF'] and dirname() to make an absolute URI from a relative one yourself:

There is more information here: http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.30

I don't know for sure, but the client may be hiding the session cookies from the server because of the malformed Location parameter. If you want to help find the common denominator:

session_start();

if (empty($_SESSION['username']))
{
    file_put_contents('/path/to/logfile.log', $_SERVER['HTTP_REFERER'], FILE_APPEND);
    header ("Location: logout.htm");
    exit();
}

The example is just a helper to see if you can spot similarities between problem browsers. Not recommended for permanent production use.