[RESOLVED] Unhelpful session error

baffled_in_UK

Hello,

I have encountered the following error message :

Warning: Unknown(): Your script possibly relies on a session side-effect which existed until PHP 4.2.3. Please be advised that the session extension does not consider global variables as a source of data, unless register_globals is enabled. You can disable this functionality and this warning by setting session.bug_compat_42 or session.bug_compat_warn to off, respectively. in Unknown on line 0

Now I've never seen that before and it's a fairly unhelpful message (well I think so anyway). My session values are the same as I use on many sites and I don't get this error. These are the session values :

<?
session_save_path('/home/sites/domain/public_html/pathsess');
session_start();  

if ($sess_id=="") { 
session_register('sess_id'); 
session_register('order_details'); 
$sess_id=session_id();  

} 
extract ($_GET); extract ($_POST)

?>

The weird thing is that it doesn't stop the site from working exactly as it should.

Any help/advice/pointers is much appreciated.
Thanks

leatherback

If you have a look at the manual for session_register(), you will see that the error message fits exactly with their giudelines.

http://uk.php.net/session_register

Caution

If you want your script to work regardless of register_globals, you need to instead use the $SESSION array as $SESSION entries are automatically registered. If your script uses session_register(), it will not work in environments where the PHP directive register_globals is disabled.

NogDog

I believe it's related to the use of session_register(). From http://www.php.net/manual/en/ref.session.php:

session.bug_compat_42 boolean
[indent]PHP versions 4.2.3 and lower have an undocumented feature/bug that allows you to initialize a session variable in the global scope, albeit register_globals is disabled. PHP 4.3.0 and later will warn you, if this feature is used, and if session.bug_compat_warn is also enabled. This feature/bug can be disabled by disabling this directive.[/indent]
session.bug_compat_warn boolean
[indent]PHP versions 4.2.3 and lower have an undocumented feature/bug that allows you to initialize a session variable in the global scope, albeit register_globals is disabled. PHP 4.3.0 and later will warn you, if this feature is used by enabling both session.bug_compat_42 and session.bug_compat_warn.[/indent]

...and...

There is a defect in PHP 4.2.3 and earlier. If you register a new session variable by using session_register(), the entry in the global scope and the $SESSION entry will not reference the same value until the next session_start(). I.e. a modification to the newly registered global variable will not be reflected by the $SESSION entry. This has been corrected in PHP 4.3.

So, you can either mess with those two php.ini settings, above, or migrate away from the now-deprecated use of session_register() and register_globals and instead use the $_SESSION array to save and read session values.

baffled_in_UK

Thanks guys.

As always, knew I'd get the amswer here 🙂