a PHP function to sniff the user agent of the browser and return a nice object with all the information

getBrowser.php

<?php
// http://www.php.net/manual/en/function.get-browser.php#101125
function getBrowser() {
  $u_agent = $_SERVER['HTTP_USER_AGENT'];
  $bname = 'Unknown';
  $platform = 'Unknown';
  $version= "";

  // First get the platform?
  if (preg_match('/linux/i', $u_agent)) {
    $platform = 'linux';
  } elseif (preg_match('/macintosh|mac os x/i', $u_agent)) {
    $platform = 'mac';
  } elseif (preg_match('/windows|win32/i', $u_agent)) {
    $platform = 'windows';
  }

  // Next get the name of the useragent yes seperately and for good reason
  if(preg_match('/MSIE/i',$u_agent) && !preg_match('/Opera/i',$u_agent)) {
    $bname = 'Internet Explorer';
    $ub = "MSIE";
  } elseif(preg_match('/Firefox/i',$u_agent)) {
    $bname = 'Mozilla Firefox';
    $ub = "Firefox";
  } elseif(preg_match('/Chrome/i',$u_agent)) {
    $bname = 'Google Chrome';
    $ub = "Chrome";
  } elseif(preg_match('/Safari/i',$u_agent)) {
    $bname = 'Apple Safari';
    $ub = "Safari";
  } elseif(preg_match('/Opera/i',$u_agent)) {
    $bname = 'Opera';
    $ub = "Opera";
  } elseif(preg_match('/Netscape/i',$u_agent)) {
    $bname = 'Netscape';
    $ub = "Netscape";
  }

  // finally get the correct version number
  $known = array('Version', $ub, 'other');
  $pattern = '#(?<browser>' . join('|', $known) . ')[/ ]+(?<version>[0-9.|a-zA-Z.]*)#';
  if (!preg_match_all($pattern, $u_agent, $matches)) {
    // we have no matching number just continue
  }

  // see how many we have
  $i = count($matches['browser']);
  if ($i != 1) {
    //we will have two since we are not using 'other' argument yet
    //see if version is before or after the name
    if (strripos($u_agent,"Version") < strripos($u_agent,$ub)){
      $version= $matches['version'][0];
    } else {
      $version= $matches['version'][1];
    }
  } else {
    $version= $matches['version'][0];
  }

  // check if we have a number
  if ($version==null || $version=="") {$version="?";}

return array(
  'userAgent' => $u_agent,
  'name'      => $bname,
  'version'   => $version,
  'platform'  => $platform,
  'pattern'    => $pattern
  );
}

// now try it
$ua = getBrowser();

Why not work for Internet explorer 11 or ... ?