(PECL pecl_http:0.1.0-1.5.5)
http_match_modified — Match last modification
Matches the given Unix timestamp against the clients If-Modified-Since resp. If-Unmodified-Since HTTP headers.
Unix timestamp; current time, if omitted
if set to TRUE, the header usually used to validate HTTP ranges will be checked
Returns TRUE if timestamp represents an earlier date than the header, else FALSE.