如何通过中断ctrl+c来关闭主线程之前的所有线程？

import threading
import signal
import sys

# 全局变量，控制线程的运行状态
running = True

# 信号处理函数
def signal_handler(signal, frame):
    global running
    print('Ctrl+C pressed. Stopping all threads...')
    running = False

# 子线程函数
def worker():
    while running:
        # 线程执行的任务
        pass

# 注册信号处理函数
signal.signal(signal.SIGINT, signal_handler)

# 创建并启动子线程
threads = []
for i in range(5):
    t = threading.Thread(target=worker)
    t.start()
    threads.append(t)

# 等待所有子线程结束
for t in threads:
    t.join()

print('All threads stopped. Exiting...')
sys.exit(0)