侦听给定端口的程序

Question

在主代码执行开始之前，我想检查一个特定的端口是否打开，如果是，那么关闭端口以便代码可以“干净地”启动。

所以我在网上谷歌和这里找到代码： http://www.paulwhippconsulting.com.au/tips/63-finding-and-killing-processes-on-ports

但是从那里只是粘贴代码：

import os 
import subprocess 
import re 

ports = ['1234','5678','9101'] 


popen = subprocess.Popen(['netstat', '-lpn'], 
         shell=False, 
         stdout=subprocess.PIPE) 
(data, err) = popen.communicate() 

pattern = "^tcp.*((?:{0})).* (?P[0-9]*)/.*$" 
pattern = pattern.format(')|(?:'.join(ports)) 
prog = re.compile(pattern) #<---- error line 
for line in data.split('\n'): 
    match = re.match(prog, line) 
    if match: 
     pid = match.group('pid') 
     subprocess.Popen(['kill', '-9', pid]) 

但它抛出一个错误。

raise error, v # invalid expression 
sre_constants.error: unknown specifier: ?P[ 

Answer 1

发布该代码段的人忘记了HTML - 转义他的代码！正确的代码如下：

import os 
import subprocess 
import re 

ports = ['1234','5678','9101'] 


popen = subprocess.Popen(['netstat', '-lpn'], 
         shell=False, 
         stdout=subprocess.PIPE) 
(data, err) = popen.communicate() 

pattern = "^tcp.*((?:{0})).* (?P<pid>[0-9]*)/.*$" 
pattern = pattern.format(')|(?:'.join(ports)) 
prog = re.compile(pattern) 
for line in data.split('\n'): 
    match = re.match(prog, line) 
    if match: 
     pid = match.group('pid') 
     subprocess.Popen(['kill', '-9', pid]) 

注意<pid>遵循?P。