Same variable for everyone php?

Question

I was wondering, is there a way to have a sort of variable that would be 'static' meaning that it would be the same for all users in php ? I know that there is a possibility to have a static variable within a function in php but that is not what I want.

I would like everyone to share an object which I would manipulate depending on the user's demand. Or, another example that is similar to what I want is, is there a way to keep a variable that counts the number of visitors (without using any sort of file or database manipulation). That variable would be incremented every time a user come to my page.

Cheers !

Answer 1

Without using a file or database, I believe you could do this using something like APC.

$var = 1;
$key = 'myVariable';
apc_store($key, $var);
echo apc_fetch($key); // 1

If you want to increment it, you can use apc_inc()

echo apc_inc($key); // 2

However, this variable won't be preserved if the cache is cleared (which happens when it fills up or the server is restarted).

Answer 2

Check out semaphores and shared memory and how they work in PHP. With a shared memory variable different processes (users) can use the same memory space and use the same variables. Here's a link to the PHP documentation to get you started:

http://www.php.net/manual/en/function.shm-get-var.php