Question

import sys 
import time
import threading

class exThread(threading.Thread):
    def __init__(self, threadId):
        threading.Thread.__init__(self)
        self.threadId = threadId

    def run(self):
        try:
            while 1:
                pass
        except KeyboardInterrupt:
            print "Ctrl-C caught by thread"
        finally:
            print "Thread's finally clause being executed" 
            sys.exit() # Same as thread.exit()

cond = True
def func():
    pass

try:
    th = exThread(1)
    th.start()
    while True:
        if cond:
            func()
except KeyboardInterrupt:
    print "Ctrl-C caught by main thread"
    sys.exit(0)
finally:
    print "Executing the finally clause from main thread"

在执行上面的代码时，当我按下Ctrl-C时，主线程在从finally子句打印后退出。现在，由于子线程是非守护进程，它仍然在try：除KeyboardInterrupt块之外运行。但是，这个子线程似乎没有响应Ctrl-C，即使它应该捕获KeyboardInterrupt异常。为什么呢？

Answer 1

据我所知，KeyboardInterrup仅在主线程中引发。为了能够阻止其他线程，让他们不时检查一个事件，然后自愿退出。

另一种选择是将子线程标记为daemon=True，以便在主线程终止时自动终止：

th.daemon = True

补充阅读：

守护程序线程如何工作Daemon Threads Explanation
但是，守护程序线程可能有害：http://joeshaw.org/2009/02/24/605/

Python 2.7：子线程没有捕获KeyboardInterrupt

1 个答案: