Warning: Undefined index: HTTP_REFERER in d:\work\web sites\... on line 24

[WestWind]

Hi,

I have inserted the code below into a site of mine to track where viewers came from (the referring page, if any) but on some pages I get the following warning:

Warning: Undefined index: HTTP_REFERER in d:\work\web sites\staffords5\mod-top on line 24

Here's the code:

<?

//traffic referrer - reports where last page visitor was at, if any

//get current date and time
$month = date("M");
$day = date("d");
$year = date("Y");
$time = ":".date("H").":".date("i").":".date("s");

//get information
$date = "[".$day."/".$month."/".$year.$time."]";
$referer = $_SERVER["HTTP_REFERER"];

//write to flat file if we have a defined referring page
$data = $date." - ".$referer."\n";
$filename = "./logs/".$year.$month.".log";
$fp=fopen($filename, "a");
fwrite($fp, $data);
fclose($fp);

?>

There must be a way of handling the undefined index without throwing a warning on my local system. I have searched for a bit but am not coming up with anything particularly useful yet.

My web provider must have warnings turned off as they don't show on the production server. However, I would prefer to resolve this warning on my local server.

Any advice appreciated,

Thanks,

-Steve

[zhabala]

if ( isset($_SERVER['HTTP_REFERER']) and !empty($_SERVER['HTTP_REFERER']) ) {
    $referer = $_SERVER['HTTP_REFERER'];
} else {
    $referer = 'Not set';
}