ip stored in file

<?php
    $ip = $_SERVER['REMOTE_ADDR'];
    $file = 'user_info.php';
    $addresses = array();
    if (file_exists($file)) {
        include($file);
    }
    // example usage
    if (isset($addresses[$ip])) {
       $addresses[$ip]['Status'] = 'Off';
       $addresses[$ip]['Name'] = 'My_Fancy_Name';
    }
    file_put_contents($file, '<'.'?php $addresses = '.var_export($addresses,true));
?>

http://stackoverflow.com/questions/11587675/php-replace-string-in-file