(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 설정 http.log.cache is set and the cache attempt was successful.
Note: 이 함수는 다음 함수와 함께 사용할 수 있습니다: http_send_data(), http_seld_file() 그리고 http_send_stream().
Unix timestamp
성공시 FALSE를 반환하거나 종료합니다. with 304 Not Modified if the entity is cached. "exits"의 의미에 대해서 INI 설정 http.force_exit를 참고하십시오.
Example #1 A http_cache_last_modified() example
Caching for 5 seconds.
<?php
http_cache_last_modified(-5);
printf("%s\n", http_date());
?>