session_cache_limiter
(PHP 4 >= 4.0.3, PHP 5, PHP 7, PHP 8)
session_cache_limiter — Get and/or set the current cache limiter
Description
$value = null): string|falsesession_cache_limiter() returns the name of the current cache limiter.
The cache limiter defines which cache control HTTP headers are sent to
the client. These headers determine the rules by which the page content
may be cached by the client and intermediate proxies. Setting the cache
limiter to nocache disallows any client/proxy caching.
A value of public permits caching by proxies and the
client, whereas private disallows caching by proxies
and permits the client to cache the contents.
In private mode, the Expire header sent to the client
may cause confusion for some browsers, including Mozilla.
You can avoid this problem by using private_no_expire mode. The
Expire header is never sent to the client in this mode.
Setting the cache limiter to '' will turn off automatic sending
of cache headers entirely.
The cache limiter is reset to the default value stored in session.cache_limiter at request startup time. Thus, you need to call session_cache_limiter() for every request (and before session_start() is called).
Parameters
-
value -
If
valueis specified and notnull, the name of the current cache limiter is changed to the new value.Possible values Value Headers sent publicExpires: (sometime in the future, according session.cache_expire) Cache-Control: public, max-age=(sometime in the future, according to session.cache_expire) Last-Modified: (the timestamp of when the session was last saved)
private_no_expireCache-Control: private, max-age=(session.cache_expire in the future), pre-check=(session.cache_expire in the future) Last-Modified: (the timestamp of when the session was last saved)
privateExpires: Thu, 19 Nov 1981 08:52:00 GMT Cache-Control: private, max-age=(session.cache_expire in the future), pre-check=(session.cache_expire in the future) Last-Modified: (the timestamp of when the session was last saved)
nocacheExpires: Thu, 19 Nov 1981 08:52:00 GMT Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0 Pragma: no-cache
Return Values
Returns the name of the current cache limiter.
On failure to change the value, false is returned.
Changelog
| Version | Description |
|---|---|
| 8.0.0 |
value is nullable now.
|
Examples
Example #1 session_cache_limiter() example
<?php
/* set the cache limiter to 'private' */
session_cache_limiter('private');
$cache_limiter = session_cache_limiter();
echo "The cache limiter is now set to $cache_limiter<br />";
?>
