python编写的一个简单的扫描端口的程序

#-------------------------------------------------------------------------------
# Name:        PortScan
# Purpose:     扫描目标主机的端口开放情况
#
# Author:      xxh
#
# Created:     05-12-2011
# Copyright:   (c) xxh 2011
# Licence:     <your licence>
#-------------------------------------------------------------------------------
#!/usr/bin/env python
 
import socket
 
def main():
    sk = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
    sk.settimeout(1000)
    ip=input('请输入目标主机：(默认:127.0.0.1)')
    if ip=='':
        ip='127.0.0.1'
 
 
 
    s=input('请输入目标主机开始端口：(默认:80)')
    if s=='':
        startport=80
    else:
        startport=int(s)
 
    s=input('请输入目标主机结束端口：(默认:80)')
    if s=='':
        endport=80
    else:
        endport=int(s)
 
    for port in range(startport,endport+1):
        print('正在扫描端口：%d' % port)
        try:
            sk.connect((ip,port))
            print('Server %s port %d OK!' % (ip,port))
        except Exception:
            print('Server %s port %d is not connected!' % (ip,port))
    sk.close()
 
 
if __name__ == '__main__':
    main()