php记录百度和google蜘蛛爬行程序代码日志

<?php
 $useragent = addslashes(strtolower($_SERVER['HTTP_USER_AGENT']));
if (strpos($useragent, 'googlebot')!== false){$bot = 'Google';}
elseif (strpos($useragent,'baiduspider') !== false){$bot = 'Baidu';}
if(isset($bot)){
$fp = @fopen('bot.txt','a');
fwrite($fp,date('Y-m-d H:i:s')."\t".$bot."\t".'http://'.$_SERVER['SERVER_NAME'].$_SERVER["REQUEST_URI"]."\r\n");
fclose($fp);
}
?>