python杀死一个线程的方法-Python Tutorial-php.cn

最近在项目中遇到这一需求：

我需要一个函数工作，比如远程连接一个端口，远程读取文件等，但是我给的时间有限，比如，4秒钟如果你还没有读取完成或者连接成功，我就不等了，很可能对方已经宕机或者拒绝了。这样可以批量做一些事情而不需要一直等，浪费时间。

结合我的需求，我想到这种办法：

1、在主进程执行，调用一个进程执行函数，然后主进程sleep，等时间到了，就kill 执行函数的进程。

测试一个例子：

import time 
import threading 
def p(i): 
  print i 
class task(threading.Thread): 
  def __init__(self,fun,i): 
    threading.Thread.__init__(self) 
    self.fun = fun 
    self.i = i 
    self.thread_stop = False 
  def run(self): 
    while not self.thread_stop: 
      self.fun(self.i) 
  def stop(self): 
    self.thread_stop = True 
def test(): 
  thread1 = task(p,2) 
  thread1.start() 
  time.sleep(4) 
  thread1.stop() 
  return 
if __name__ == '__main__': 
  test()

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经过测试只定了4秒钟。

经过我的一番折腾，想到了join函数，这个函数式用来等待一个线程结束的，如果这个函数没有结束的话，那么，就会阻塞当前运行的程序。关键是，这个参数有一个可选参数：join([timeout]): 阻塞当前上下文环境的线程，直到调用此方法的线程终止或到达指定的timeout（可选参数）。

不多说了贴下面代码大家看下：

#!/usr/bin/env python 
#-*-coding:utf-8-*- 
''''' 
author:cogbee 
time:2014-6-13 
function:readme 
''' 
import pdb 
import time 
import threading 
import os 
#pdb.set_trace() 
class task(threading.Thread): 
  def __init__(self,ip): 
    threading.Thread.__init__(self) 
    self.ip = ip 
    self.thread_stop = False 
  def run(self): 
    while not self.thread_stop:   
      #//添加你要做的事情，如果成功了就设置一下<span style="font-family: Arial, Helvetica, sans-serif;">self.thread_stop变量。</span> 
[python] view plaincopy在CODE上查看代码片派生到我的代码片
      if file != '': 
        self.thread_stop = True 
  def stop(self): 
    self.thread_stop = True 
def test(eachline): 
  global file 
  list = [] 
  for ip in eachline: 
    thread1 = task(ip) 
    thread1.start() 
    thread1.join(3) 
    if thread1.isAlive():   
      thread1.stop() 
      continue 
    #将可以读取的都存起来 
    if file != '': 
      list.append(ip) 
  print list 
if __name__ == '__main__': 
  eachline = ['1.1.1.1','222.73.5.54'] 
  test(eachline)

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下面给大家分享我写的一段杀死线程的代码。

由于python线程没有提供abort方法，分享下面一段代码杀死线程：

import threading 
import inspect 
import ctypes 
def _async_raise(tid, exctype):
  """raises the exception, performs cleanup if needed"""
  if not inspect.isclass(exctype):
    raise TypeError("Only types can be raised (not instances)")
  res = ctypes.pythonapi.PyThreadState_SetAsyncExc(tid, ctypes.py_object(exctype))
  if res == 0:
    raise ValueError("invalid thread id")
  elif res != 1:
    # """if it returns a number greater than one, you're in trouble, 
    # and you should call it again with exc=NULL to revert the effect"""
    ctypes.pythonapi.PyThreadState_SetAsyncExc(tid, 0)
    raise SystemError("PyThreadState_SetAsyncExc failed")
class Thread(threading.Thread):
  def _get_my_tid(self):
    """determines this (self's) thread id"""
    if not self.isAlive():
      raise threading.ThreadError("the thread is not active")
    # do we have it cached&#63;
    if hasattr(self, "_thread_id"):
      return self._thread_id
    # no, look for it in the _active dict
    for tid, tobj in threading._active.items():
      if tobj is self:
        self._thread_id = tid
        return tid
    raise AssertionError("could not determine the thread's id")
def raise_exc(self, exctype):
    """raises the given exception type in the context of this thread"""
    _async_raise(self._get_my_tid(), exctype)
def terminate(self):
    """raises SystemExit in the context of the given thread, which should 
    cause the thread to exit silently (unless caught)"""
    self.raise_exc(SystemExit)

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使用例子：

>>> import time 
>>> from thread2 import Thread 
>>> 
>>> def f(): 
...   try: 
...     while True: 
...       time.sleep(0.1) 
...   finally: 
...     print "outta here" 
... 
>>> t = Thread(target = f) 
>>> t.start() 
>>> t.isAlive() 
True 
>>> t.terminate() 
>>> t.join() 
outta here 
>>> t.isAlive() 
False

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试了一下，很不错，只是在要kill的线程中如果有time.sleep()时，好像工作不正常，没有找出真正的原因是什么。已经是很强大了。哈哈。

Related labels：

python杀死线程 python线程

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