Changing PHP session variable

Question

I'm experiencing a strange PHP session issue. Can someone tell me if that's how session works?

To see the problem, load the following code into any php file, say test.php, and run it 2 times. NOTE, you have to run it two times, i.e. load the page and reload it.

<?
session_start();
$_SESSION["test"] = "Original////";
$test=$_SESSION["test"];
echo $_SESSION["test"];
$test="New////";
echo $_SESSION["test"];
?>

On my server, the first time I load this test page, I get

Original////Original////

and that is correct. But when I reload it, I get

Original////New////

which means the 5th line "$test="New////";" actually rewrite my $_SESSION["test"]. That doesn't make sense to me. Anyone knows what is happening? Or it's just happening on my server???

That indeed should not be happening. Is this the entire code? No references used anywhere? More code that changes the value later on? — deceze
– deceze ♦, Commented Nov 30, 2012 at 10:45
Can't think of a reason that would be happening unless you have only given us a segment of the code... — Chris
– Chris, Commented Nov 30, 2012 at 10:46
Please make sure that register_globals isn't enabled on your server. — user399666
– user399666, Commented Nov 30, 2012 at 10:47
Tested that code on my machine, hit refresh I get Original////Original//// each time. — Chris
– Chris, Commented Nov 30, 2012 at 10:48

user399666 · Accepted Answer · 2012-11-30 10:48:28Z

6

Seems like register_globals is enabled on your server. You'll need to disable the directive.

answered Nov 30, 2012 at 10:48

user399666

20k7 gold badges49 silver badges68 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

user557846 Over a year ago

nice catch,, so long since i have seen a server with that on, you just don't think about it any more.

user399666 Over a year ago

@Dagon Got caught out by it last year. Host had a "misconfiguration". Suffice to say, I tore my hair out for a while before I figured it out.

Tomasz Kowalczyk · Accepted Answer · 2012-11-30 10:52:00Z

1

Firstly, do not use <? as a starting tag of PHP, please use <?php. Secondly, this is an expected behavior if you have register_globals enabled. Look at this link:

http://www.theblog.ca/session-register-globals

It's title says:

When register_globals is on, session variables overwrite global variables

And sample code is similar to yours:

<?php
session_start();
$canadaday = 'July 1st';
$_SESSION['canadaday'] = 'July 2nd';

print '<p>When is Canada Day?</p>';
print '<p><strong>' . $canadaday . '</strong></p>';
?>

With register_globals, result is July 2nd. HTH.

answered Nov 30, 2012 at 10:52

Tomasz Kowalczyk

10.5k6 gold badges56 silver badges70 bronze badges

Comments

Gurhar · Accepted Answer · 2012-11-30 10:53:03Z

-2

<?php
session_start();
$_SESSION["test"] = "Original////";
$test=$_SESSION["test"];
echo $_SESSION["test"];
$test="New////";
echo $_SESSION["test"];
?>

I have tried your code in my environment its running perfectly.its always print Original////Original//// so its happening only on your server

answered Nov 30, 2012 at 10:53

Gurhar

1

1 Comment

Tomasz Kowalczyk Over a year ago

-1, you don't have register_globals enabled that's why it "works for you".

Collectives™ on Stack Overflow

Changing PHP session variable

3 Answers 3

2 Comments

Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related