Question

I’m trying to redirect users to different pages based on OS but keep getting this warning:

PHP Warning: preg_match() [function.preg-match]: Unknown modifier ‘2’ in /index.php on line 292

It only seems to happen with Windows NT 5.1 and MSIE 8.0 browser configuration:

function getOS($userAgent) {
  // Create list of operating systems with operating system name as array key 
    $oses = array (
        'iPhone' => '(iPhone)',
        'iPad' => 'iPad',
        'Android' => 'Android',
        'Windows 3.11' => 'Win16',
        'Windows 95' => '(Windows 95)|(Win95)|(Windows_95)', // Use regular expressions as value to identify operating system
        'Windows 98' => '(Windows 98)|(Win98)',
        'Windows 2000' => '(Windows NT 5.0)|(Windows 2000)',
        'Windows XP' => '(Windows NT 5.1)|(Windows XP)',
        'Windows 2003' => '(Windows NT 5.2)',
        'Windows Vista' => '(Windows NT 6.0)|(Windows Vista)',
        'Windows 7' => '(Windows NT 6.1)|(Windows 7)',
        'Windows NT 4.0' => '(Windows NT 4.0)|(WinNT4.0)|(WinNT)|(Windows NT)',
        'Windows ME' => 'Windows ME',
        'Blackberry' => 'Blackberry',
        'Open BSD'=>'OpenBSD',
        'Sun OS'=>'SunOS',
        'Linux'=>'(Linux)|(X11)',

        'Macintosh'=>'(Mac_PowerPC)|(Macintosh)',
        'QNX'=>'QNX',
        'BeOS'=>'BeOS',
        'OS/2'=>'OS/2',
        'Search Bot'=>'(nuhk)|(Googlebot)|(Yammybot)|(Openbot)|(Slurp/cat)|(msnbot)|(ia_archiver)'
    );
    //'Safari' => '(Safari)',
foreach($oses as $os=>$pattern){ // Loop through $oses array
    // Use regular expressions to check operating system type

    if(preg_match("/".$pattern."/i", $userAgent)) { 
            // Check if a value in $oses array matches current 
            //user agent. <---- Line 292

Tried removing OS/2 and changing to OS2 but still redirects to the wrong page for MSIE 8 with Windows XP

Answer 1

problem is with OS/2 and using / as your delimeter. You can just escape the forwardslash like OS\/2 and it should work.