PHP 检测因特网址是否能正常打开代码

<meta charset="utf-8"><?php function httpcode($url){	$ch = curl_init();	$timeout = 3;	curl_setopt($ch,CURLOPT_FOLLOWLOCATION,1);	curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);	curl_setopt($ch, CURLOPT_HEADER, 1);	curl_setopt ($ch, CURLOPT_CONNECTTIMEOUT, $timeout); 	curl_setopt($ch,CURLOPT_URL,$url);	curl_exec($ch);	return $httpcode = curl_getinfo($ch,CURLINFO_HTTP_CODE);	curl_close($ch);  }?>使用方法：<?php echo httpcode('http://www.onestopweb.cn');?> 如果显示为200则正常，如果显示其它值表示不正常；$timeout后面的3是设置超时秒数。