python的socket库可以检测端口是否开放

import socket;  sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)  result = sock.connect_ex(('127.0.0.1',80))  if result == 0:     print "Port is open"  else:     print "Port is not open"

这里sock.connect_ex方法尝试连接如果连接成功返回0。