python - 键盘中断、套接字和线程

Question

我正在开发一个使用套接字进行通信的接口(interface)。我需要使用线程才能同时接收和发送数据。

下面的代码是连续发送数据的模块的简化版本。

我的问题是，在开发过程中，我需要频繁地启动和停止，但线程似乎无法像普通脚本那样停止应用程序。该进程需要在进程管理器中终止才能重新启动。

我感觉我误解了一些东西。

我环顾四周，但看到大量不一致的答案，我尝试实现这些答案却无济于事。我尝试过处理 KeyboardInterrupt 异常，但不起作用。

有什么想法吗？

import socket
import sys
import threading

running = True
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

server_address = ('localhost', 50000)
print ('connecting to %s port %s' % server_address)
sock.connect(server_address)

class TelemetryPacket:
    state = "N/A" 

    def __init__(self, stringvalue):
        self.state = stringvalue

    def serialise(self):
        return "%s" % (self.state)

def send(running):
    try:
        while (running):
            telemetry = TelemetryPacket(0).serialise()
            sock.sendto(telemetry.encode('utf-8'), server_address)
    except KeyboardInterrupt:
        print ("threads successfully closed")
        running = False

def recv(running):
    try:
        while (running):
            data = sock.recv(1)
            if (data):
                print("data received: %s" % data)
    except KeyboardInterrupt:
        print ("threads successfully closed")
        running = False

a = threading.Thread(target=send, args=(running,))
a.start()

b = threading.Thread(target=recv, args=(running,))
b.start()

Answer 1

您应该在主线程中捕获键盘中断，然后向子线程发送信号以退出并重新加入主线程。您还应该使用更线程安全的信号来发送信号，例如基本的 threading.Event()，因此:

import threading
import time

exit_signal = threading.Event()  # your global exit signal

def send():
    while not exit_signal.is_set():
        pass  # whatever you need

def recv():
    while not exit_signal.is_set():
        pass  # whatever you need

# create the threads
a = threading.Thread(target=send)
b = threading.Thread(target=recv)

# start the threads
a.start()
b.start()

# create a main thread loop
try:
    while not exit_signal.is_set():  # enable children threads to exit the main thread, too
        time.sleep(0.1)  # let it breathe a little
except KeyboardInterrupt:  # on keyboard interrupt...
    exit_signal.set()  # send signal to all listening threads

# join back the threads
a.join()
b.join()

# and you're done...