如何从 socket.timeout 异常处理程序中捕获 KeyboardInterrupt？答案

【问题标题】：How to catch KeyboardInterrupt from within socket.timeout exception handler?如何从 socket.timeout 异常处理程序中捕获 KeyboardInterrupt？
【发布时间】：2017-04-15 01:30:05
【问题描述】：

我正在尝试开发一个简单的套接字服务器，它具有非阻塞接受（使用 settimeout），但我希望能够使用 Ctrl-C（键盘中断）停止它。

我的代码是这样的：

import socket

host = '127.0.0.1'
port = 5000

s = socket.socket()
s.settimeout(1)
s.bind((host, port))
s.listen(1)
print('Server started')
while True:
    try:
        conn, addr = s.accept()
    except socket.timeout:
        pass
    except Exception as exc:
        print(str(exc))
        print('Server closing')
        s.close()
        break
    except KeyboardInterrupt:
        print('Server closing')
        s.close()
        break
    else:
        print('Connection from', addr)

但是 KeyboardInterrupt 永远不会被捕获，因为它发生在 socket.timeout 异常处理程序中。这是按 Ctrl-C 时的输出

c:\Users\JMatos\MEOCloud\Python>python file_server.py
Server started
Traceback (most recent call last):
  File "file_server.py", line 40, in <module>
    conn, addr = s.accept()
  File "C:\Python35-32\lib\socket.py", line 195, in accept
    fd, addr = self._accept()
socket.timeout: timed out

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "file_server.py", line 40, in <module>
    conn, addr = s.accept()
KeyboardInterrupt

有没有办法在 socket.timeout 异常处理程序中捕获 KeyboardInterrupt 异常？

我的环境是 Windows 7P+SP1 x64，Python 3.5.2 32b。

提前致谢，

【问题讨论】：

标签： python python-3.x sockets settimeout keyboardinterrupt

【解决方案1】：

问题不在于套接字超时。问题是您期望抛出异常的地方。将代码更改为：

try:
    while True:
        try:
            conn, addr = s.accept()
        except socket.timeout:
             pass
        except Exception as exc:
             print(str(exc))
             print('Server closing')
             s.close()
             break
    else:
        print('Connection from', addr)
except KeyboardInterrupt:
    print('Server closing')
    s.close()

【讨论】：

谢谢，成功了。