(PECL pecl_http >= 0.1.0)
http_cache_last_modified — Caching by last modification
Attempts to cache the sent entity by its last modification date.
If the supplied argument is greater than 0, it is handled as timestamp and will be sent as date of last modification. If it is 0 or omitted, the current time will be sent as Last-Modified date. If it's negative, it is handled as expiration time in seconds, which means that if the requested last modification date is not between the calculated timespan, the Last-Modified header is updated and the actual body will be sent.
A log entry will be written to the cache log if the INI настройка http.log.cache is set and the cache attempt was successful.
Забележка: Тази функция може да се използва в комбинация с http_send_data(), http_send_file() и http_send_stream().
Unix timestamp
Връща FALSE или излиза при успех with 304 Not Modified if the entity is cached. Вижте INI настройка http.force_exit за да разберете какво означава "излиза".
Example #1 A http_cache_last_modified() example
Caching for 5 seconds.
<?php
http_cache_last_modified(-5);
printf("%s\n", http_date());
?>