(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)
session_cache_expire — Get and/or set current cache expire
session_cache_expire() returns the current setting of
session.cache_expire.
The cache expire is reset to the default value of 180 stored in session.cache_expire at request startup time. Thus, you need to call session_cache_expire() for every request (and before session_start() is called).
value
If value is given and not null, the current cache
expire is replaced with value.
Note: Setting
valueis of value only, ifsession.cache_limiteris set to a value different fromnocache.
Returns the current setting of session.cache_expire.
The value returned should be read in minutes, defaults to 180.
On failure to change the value, false is returned.
| Version | Description |
|---|---|
| 8.0.0 |
value is nullable now.
|
Example #1 session_cache_expire() example
<?php
/* set the cache limiter to 'private' */
session_cache_limiter('private');
$cache_limiter = session_cache_limiter();
/* set the cache expire to 30 minutes */
session_cache_expire(30);
$cache_expire = session_cache_expire();
/* start the session */
session_start();
echo "The cache limiter is now set to $cache_limiter<br />";
echo "The cached session pages expire after $cache_expire minutes";
?>
The manual probably doesn't stress this enough:
** This has nothing to do with lifetime of a session **
Whatever you set this setting to, it won't change how long sessions live on your server.
This only changes HTTP cache expiration time (Expires: and Cache-Control: max-age headers), which advise browser for how long it can keep pages cached in user's cache without having to reload them from the server.Using PHP 8.2
session_start();
$result1 = session_cache_expire( 30 ); // setter, results in Warning: Session cache expiration cannot be changed when a session is active in ...
$result2 = session_cache_expire(); // getter
var_dump( $result1, $result2 ); // prints out: int(180) int(180) [note: 180 is the default value]
Because the session was already started, cache expiration could not be changed (warning message). However, the return value is NOT false, it is still the original, unchanged value!
So I do not know what is considered a failure to change the value as per the documentation (`On failure to change the value, false is returned.`).