python杀死一个线程的方法

时间:2022-11-02 16:23:06

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:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
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()

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:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
#!/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)

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:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
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?
    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)

使用例子:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
>>> 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

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。