Implementing a Visitor Tracking System

Question

For my website I want a track visitor system

I found this one HERE But after setting it up, I get an error.

Fatal error: Cannot redeclare getBrowserType() (previously declared

I also don't know where the first bunch of code has to go. On the page you want to track or somewhere else?

EDIT*

After deleting the code bellow it worked. But visitor page and visitor date in MySQL database are empty. Where should I put this code? And I should change something right? It's otherwise double and nothing will work:

function getBrowserType () {
if (!empty($_SERVER['HTTP_USER_AGENT']))
{
   $HTTP_USER_AGENT = $_SERVER['HTTP_USER_AGENT'];
}
else if (!empty($HTTP_SERVER_VARS['HTTP_USER_AGENT']))
{
   $HTTP_USER_AGENT = $HTTP_SERVER_VARS['HTTP_USER_AGENT'];
}
else if (!isset($HTTP_USER_AGENT))
{
   $HTTP_USER_AGENT = '';
}
if (ereg('Opera(/| )([0-9].[0-9]{1,2})', $HTTP_USER_AGENT, $log_version))
{
   $browser_version = $log_version[2];
   $browser_agent = 'opera';
}
else if (ereg('MSIE ([0-9].[0-9]{1,2})', $HTTP_USER_AGENT, $log_version))
{
   $browser_version = $log_version[1];
   $browser_agent = 'ie';
}
else if (ereg('OmniWeb/([0-9].[0-9]{1,2})', $HTTP_USER_AGENT, $log_version))
{
   $browser_version = $log_version[1];
   $browser_agent = 'omniweb';
}
else if (ereg('Netscape([0-9]{1})', $HTTP_USER_AGENT, $log_version))
{
   $browser_version = $log_version[1];
   $browser_agent = 'netscape';
}
else if (ereg('Mozilla/([0-9].[0-9]{1,2})', $HTTP_USER_AGENT, $log_version))
{
   $browser_version = $log_version[1];
   $browser_agent = 'mozilla';
}
else if (ereg('Konqueror/([0-9].[0-9]{1,2})', $HTTP_USER_AGENT, $log_version))
{
   $browser_version = $log_version[1];
   $browser_agent = 'konqueror';
}
else
{
   $browser_version = 0;
   $browser_agent = 'other';
}
return $browser_agent;
}

Here is browser types code:
$visitor_browser = getBrowserType();
Now we need to define hour, minute, day, month and year of visitors:

$visitor_hour = date("h");
$visitor_minute = date("i");
$visitor_day = date("d");
$visitor_month = date("m");
$visitor_year = date("y");
And next we need to find out who is sending us visitors so we can thank them.

$visitor_refferer = gethostbyname($HTTP_REFERER);
So to get the full url of our page we will use this function:

function selfURL() {
$s = empty($_SERVER["HTTPS"]) ? '' : ($_SERVER["HTTPS"] == "on") ? "s" : "";
$protocol = strleft(strtolower($_SERVER["SERVER_PROTOCOL"]), "/").$s;
$port = ($_SERVER["SERVER_PORT"] == "80") ? "" : (":".$_SERVER["SERVER_PORT"]);
return $protocol."://".$_SERVER['SERVER_NAME'].$port.$_SERVER['REQUEST_URI'];
}
function strleft($s1, $s2) { return substr($s1, 0, strpos($s1, $s2));
}
Now we have our page, we will store it on a variable:

$visited_page = selfURL();

Answer 1

It's saying the function already exists. Either modify it to a new function name (like myGetBrowserType() ) or remove the entire function declaration, if the very same function is in use elsewhere in the project.

function myGetBrowserType () {

and then elsewhere...

[..] myGetBrowserType( [..]