Getting the right time

[grissom]

Hi all

 

I've been using the PHP time() function for a while now to time-stamp various bits of activity, but of course it relies on the server clock being set correctly, which on many servers it isn't.

 

So my question is - is there a resource somewhere on the internet which I can access directly through my PHP code which will give me a "guaranteed" exact time, rather than rely on the server clock.

 

Many thanks.

[Daniel0]

Tell your server admin to install an NTP client and adjust the time zone manually in PHP as described in this tutorial: http://www.phpfreaks.com/tutorial/working-with-dates-in-php

[Mark Baker]

If you want to do it via PHP

function query_time_server ($timeserver, $port) {
$timevalue = null;
$fp = fsockopen($timeserver, $port, $err, $errstr, 5);
if ($fp) {
	fputs($fp,"\n");
	$timevalue = fread($fp,49);
	fclose($fp);
}

$ret = array( $timevalue,
			  $err,			//	error code
			  $errstr		//	error text
			);
return($ret);
}	//	function query_time_server()


$timeserver = "time-C.timefreq.bldrdoc.gov";
$timercvd = query_time_server($timeserver,13);

if (!$timercvd[1]) {
$timevalue = $timercvd[0];
echo 'Time check from time server ',$timeserver,' : [<font color="red">',$timevalue,'</font>]';
} else {
echo 'Unfortunately, the time server $timeserver could not be reached at this time. ';
echo $timercvd[1].' '.$timercvd[2];
}

You can change the timeserver to any public ntp server

[Daniel0]

It will undoubtedly slow down his web pages if he has to wait for the response of an external third party each time.

[Mark Baker]

It will undoubtedly slow down his web pages if he has to wait for the response of an external third party each time.

True, but perhaps the timeserver script could be run periodically as a cron task, and the result used to set the system clock via an exec.... assuming that's permitted by the host configuration