python - 如何使用 Python 在后台运行方法

Question

我正在尝试在 python 后台运行一个方法(一个通过来自 aws 服务器的消息不断更新的类)，并且我使用它作为模板。问题是，我无法打印('检查点')或打印('再见')。它只是继续运行 run(self)。这是为什么？

import threading
import time


class ThreadingExample(object):
    """ Threading example class
    The run() method will be started and it will run in the background
    until the application exits.
    """

    def __init__(self, interval=1):
        """ Constructor
        :type interval: int
        :param interval: Check interval, in seconds
        """
        self.interval = interval

        thread = threading.Thread(target=self.run, args=())
        thread.daemon = True                            # Daemonize thread
        thread.start()                                  # Start the execution

    def run(self):
        """ Method that runs forever """
        while True:
            # Do something
            print('Doing something imporant in the background')

            time.sleep(self.interval)

example = ThreadingExample()
time.sleep(3)
print('Checkpoint')
time.sleep(2)
print('Bye')

编辑:我忘了提及我正在 Ubuntu 14.04 LTS 64 位上使用 Python 2.7.6

Answer 1

我已经运行了你的代码，它工作正常(python34，ubuntu14)

with thread.daemon = True:

Doing something important in the background
Doing something important in the background
Doing something important in the background
Checkpoint
Doing something important in the background
Doing something important in the background
Bye

使用守护进程 = False:

Doing something imporant in the background
Doing something important in the background
Doing something important in the background
Checkpoint
Doing something important in the background
Doing something important in the background
Bye
Doing something important in the background
Doing something important in the background
Doing something important in the background
Doing something important in the background
...