PHP判断端口是否打开的代码

 1 <?php
 2  $host = 'www.baidu.com'; //要ping的地址，也可以是IP
 3  $port = '80'; //要ping的端口
 4  $num  = 3;
 5 function microtime_float()
 6 {
 7         list($usec, $sec) = explode(" ", microtime());
 8         return ((float)$usec + (float)$sec);
 9 }
10 function ping($host,$port)
11 {
12         $time_start = microtime_float();
13         $ip = gethostbyname($host);
14         $fp = @fsockopen($host,$port,&$errno,&$errstr,1);
15         if(!$fp) return 'replay time out!';
16         $get = "GET / HTTP/1.1\r\nHost:".$host."\r\nConnection: Close\r\n\r\n";
17         @fputs($fp,$get);
18         @fclose($fp);
19         $time_end = microtime_float();
20         $time = $time_end - $time_start;
21         $time = ceil($time * 1000);
22         return 'Reply from '.$ip.': time='.$time.'ms<br />';
23 }
24 echo 'Pinging '.$host.' ['.gethostbyname($host).'] with Port:'.$port.' of data:<br /><br />'."\r\n";
25 for($i = 0;$i < $num;$i++)
26 {        
27         ping($host,$port);
28         sleep(1);
29         ob_flush();
30         flush();
31 }
32 ?>