Tarayıcı bilgilerini ögrenmek

<?php
// Browser bulma şeysi 
        if( eregi("(opera) ([0-9]{1,2}.[0-9]{1,3}){0,1}",$_SERVER['HTTP_USER_AGENT'],$regs) || 
eregi("(opera/)([0-9]{1,2}.[0-9]{1,3}){0,1}",$_SERVER['HTTP_USER_AGENT'],$regs)){$browser 
= "Opera $regs[2]";} 
        elseif( eregi("(konqueror)/([0-9]{1,2}.[0-9]{1,3})",$_SERVER 
['HTTP_USER_AGENT'],$regs) ){$browser = "Konqueror $regs[2]";} 
        elseif( eregi("(omniweb/)([0-9]{1,2}.[0-9]{1,3})",$_SERVER['HTTP_USER_AGENT'],$regs) ) 
{$browser = "OmniWeb $regs[2]";} 
        elseif( eregi("(webtv/)([0-9]{1,2}.[0-9]{1,3})",$_SERVER['HTTP_USER_AGENT'],$regs) ) 
{$browser = "WebTV $regs[2]";} 
        elseif( eregi("(lynx)/([0-9]{1,2}.[0-9]{1,2}.[0-9]{1,2})",$_SERVER 
['HTTP_USER_AGENT'],$regs) ){$browser = "Lynx $regs[2]";} 
        elseif( eregi("(links) \(([0-9]{1,2}.[0-9]{1,3})",$_SERVER['HTTP_USER_AGENT'],$regs) ) 
{$browser = "Links $regs[2]";} 
        elseif( eregi("(msie) ([0-9]{1,2}.[0-9]{1,3})",$_SERVER['HTTP_USER_AGENT'],$regs) ) 
{$browser = "MSIE $regs[2]";} 
        elseif( eregi("(netscape6)/(6.[0-9]{1,3})",$_SERVER['HTTP_USER_AGENT'],$regs) ) 
{$browser = "Netscape $regs[2]";} 
        elseif( eregi("mozilla/5",$_SERVER['HTTP_USER_AGENT']) ){$browser = "Netscape";} 
        elseif( eregi("(mozilla)/([0-9]{1,2}.[0-9]{1,3})",$_SERVER['HTTP_USER_AGENT'],$regs) ) 
{$browser = "Netscape $regs[2]";} 
        elseif( eregi("w3m",$_SERVER['HTTP_USER_AGENT']) ){$browser = "w3m";} 
        else{$browser = "Unknown";} 
// OS işeysi 
if(eregi("linux",$_SERVER['HTTP_USER_AGENT'])){$system = "Linux";} 
        elseif(eregi("win32",$_SERVER['HTTP_USER_AGENT'])){$system = "Windows";} 
        elseif(eregi("Win 9x 4.90",$_SERVER['HTTP_USER_AGENT'])){$system = "Windows Me";} 
elseif(eregi("windows 2000",$_SERVER['HTTP_USER_AGENT']) || eregi("(windows nt)( ){0,1} 
(5.0)",$_SERVER['HTTP_USER_AGENT']) ){$system = "Windows 2000";} 
elseif(eregi("(windows nt)( ){0,1}(5.1)",$_SERVER['HTTP_USER_AGENT']) ){$system = "Windows 
XP";} 
        elseif( (eregi("(win)([0-9]{2})",$_SERVER['HTTP_USER_AGENT'],$regs)) || (eregi 
("(windows) ([0-9]{2})",$_SERVER['HTTP_USER_AGENT'],$regs)) ){$system = "Windows $regs[2]";} 
        elseif(eregi("(winnt)([0-9]{1,2}.[0-9]{1,2}){0,1}",$_SERVER['HTTP_USER_AGENT'],$regs) ) 
{$system = "Windows NT $regs[2]";} 
        elseif(eregi("(windows nt)( ){0,1}([0-9]{1,2}.[0-9]{1,2}){0,1}",$_SERVER 
['HTTP_USER_AGENT'],$regs) ){$system = "Windows NT $regs[3]";} 
        elseif(eregi("mac",$_SERVER['HTTP_USER_AGENT'])){$system = "Macintosh";} 
        elseif(eregi("(sunos) ([0-9]{1,2}.[0-9]{1,2}){0,1}",$_SERVER 
['HTTP_USER_AGENT'],$regs)){$system = "SunOS $regs[2]";} 
        elseif(eregi("(beos) r([0-9]{1,2}.[0-9]{1,2}){0,1}",$_SERVER['HTTP_USER_AGENT'],$regs)) 
{$system = "BeOS $regs[2]";} 
        elseif(eregi("freebsd",$_SERVER['HTTP_USER_AGENT'])){$system = "FreeBSD";} 
        elseif(eregi("openbsd",$_SERVER['HTTP_USER_AGENT'])){$system = "OpenBSD";} 
        elseif(eregi("irix",$_SERVER['HTTP_USER_AGENT'])){$system = "IRIX";} 
        elseif(eregi("os/2",$_SERVER['HTTP_USER_AGENT'])){$system = "OS/2";} 
        elseif(eregi("plan9",$_SERVER['HTTP_USER_AGENT'])){$system = "Plan9";} 
        elseif(eregi("unix",$_SERVER['HTTP_USER_AGENT']) || eregi("hp-ux",$_SERVER 
['HTTP_USER_AGENT']) || eregi("X11",$_SERVER['HTTP_USER_AGENT']) ){$system = "Unix";} 
        elseif(eregi("osf",$_SERVER['HTTP_USER_AGENT'])){$system = "OSF";} 
        else{$system = "Unknown";} 
        echo "Şu an siteme $browser tarayıcı ve $system işletim sistemi ile girdin ***<br>"; 
?>

<?php
$tarayici = $_SERVER["HTTP_USER_AGENT"];
echo $tarayici
//Burada date fonksiyonu ile tarayici'yi çagırdık ve echo ile de sayfaya yazdırdık.

?>