PHP判断服务器端口是否打开的代码

记录一下，以后备用

php 
$host = 'www.google.com'; //要ping的地址，也可以是IP  
$port = '80'; //要ping的端口  
$num = 3;  
function microtime_float()  
{  
list($usec, $sec) = explode(" ", microtime());  
return ((float)$usec + (float)$sec);  
}  
function ping($host,$port)  
{  
$time_start = microtime_float();  
$ip = gethostbyname($host);  
$fp = @fsockopen($host,$port,&$errno,&$errstr,1);  
if(!$fp) return 'replay time out!';  
$get = "GET / HTTP/1.1\r\nHost:".$host."\r\nConnection: Close\r\n\r\n";  
@fputs($fp,$get);  
@fclose($fp);  
$time_end = microtime_float();  
$time = $time_end - $time_start;  
$time = ceil($time * 1000);  
return 'Reply from '.$ip.': time='.$time.'ms<br />';  
}  
echo 'Pinging '.$host.' ['.gethostbyname($host).'] with Port:'.$port.' of data:<br /><br />'."\r\n";  
for($i = 0;$i < $num;$i++)  
{  
ping($host,$port);  
sleep(1);  
ob_flush();  
flush();  
}  
?> 

本文摘自 http://www.cnblogs.com/luoine/archive/2010/12/01/1893156.html