http_cache_etag
(PECL pecl_http >= 0.1.0)
http_cache_etag — Caching by ETag
Description
$etag
] )Attempts to cache the sent entity by its ETag, either supplied or generated by the hash algorithm specified by the INI setting http.etag.mode.
If the clients If-None-Match header matches the supplied/calculated ETag, the body is considered cached on the clients side and a 304 Not Modified status code is issued.
A log entry is written to the cache log if the INI setting http.log.cache is set and the cache attempt was successful.
Note: This function may be used in conjunction with http_send_data(), http_send_file() and http_send_stream().
If this function is used outside the http_send_*() API, it facilitates the ob_etaghandler().
Parameters
-
etag -
custom ETag
Return Values
Returns FALSE or exits on success with 304 Not Modified if the entity is cached.
See the INI setting
http.force_exit for what "exits" means.
Examples
Example #1 A http_cache_etag() example
<?php
http_cache_etag();
http_send_data("data");
?>
See Also
- http_cache_last_modified() - Caching by last modification
- ob_etaghandler() - ETag output handler
- http_match_etag() - Match ETag
- the HttpResponse class if you are using PHP 5.1.0 and above
