php man page for http_send_last_modified

HTTP_SEND_LAST_MODIFIED(3)						 1						HTTP_SEND_LAST_MODIFIED(3)

http_send_last_modified - Send Last-Modified

SYNOPSIS
       bool http_send_last_modified ([int  $timestamp = time()])

DESCRIPTION
	Send a Last-Modified header with a valid HTTP date.

       Note

	      This function should be used in conjunction with http_send_data(3), http_send_file(3) and http_send_stream(3).

PARAMETERS
	      o $timestamp
		- a Unix timestamp, converted to a valid HTTP date; if omitted, the current time will be sent

RETURN VALUES
	Returns TRUE on success or FALSE on failure.

SEE ALSO
       the HttpResponse class if you are using PHP 5.1.0 and above.

PHP Documentation Group 												HTTP_SEND_LAST_MODIFIED(3)