session_cache_limiter

Get and/or set the current cache limiter

&reftitle.description; ``string``false```session_cache_limiter` ``string``null```value`&null;

`session_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).

&reftitle.parameters;

`value`

- If `value` is specified and not &null;, the name of the current cache limiter is changed to the new value.

  ## Possible values

  Value | Headers sent
  `public` |
      Expires: (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_expire` |
      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)
  `private` |
      Expires: 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)
  `nocache` |
      Expires: 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

&reftitle.returnvalues;

Returns the name of the current cache limiter. On failure to change the value, &false; is returned.

&reftitle.changelog;

&Version; | &Description;
8.0.0 | `value` is nullable now.

&reftitle.examples;

### `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 />";
    ?>

&reftitle.seealso;

- session.cache_limiter