Question

当一个线程卡在一个while循环中时，是否可以提前停止？下面是我的示例代码，它正确运行，因为每次调用loop_thread时，它都会检查是否设置了threading.Event()标志。当试图运行处理信息的文件的代码比每秒更长时间时，没有办法阻止整个函数继续执行直到下一次迭代。例如，如果我运行dld_img_thread，则需要大约5分钟才能完成执行并重新检查while循环以查看是否应继续执行。我想要的是在短于5分钟（例如1分钟）的时间内杀死dld_img_thread。我不在乎数据是否丢失，只是线程在函数完成执行之前就停止了。谢谢

import threading, time, pythoncom, read_mt0
import powerfail_debugport_reader as pf_dbg_rdr
import powerfail_firmware_downloader as pf_fwdld


def loop_thread(thread_name, thread_event):
    loopCnt = 0
    print "\nstarting {}".format(thread_name)
    print "is {0} alive? {1}\n".format(thread_name, L00P_thread.is_alive())
    while not thread_event.is_set():
        print("value of loopCnt = {}".format(loopCnt))
        loopCnt += 1
        time.sleep(1)
    print('stopping {}\n'.format(thread_name))

def image_dld(thread_name, thread_event):
    pythoncom.CoInitializeEx(pythoncom.COINIT_MULTITHREADED)
    print "\nstarting {}".format(thread_name)
    print "is {0} alive? {1}\n".format(thread_name, dld_img_thread.is_alive())
    while not thread_event.is_set():
        pf_fwdld.power_fail_test()
    print('stopping {}'.format(thread_name))

def debug_port_thread(thread_name, thread_event):
    pythoncom.CoInitializeEx(pythoncom.COINIT_MULTITHREADED)
    print "\nstarting {}".format(thread_name)
    print "is {0} alive? {1}\n".format(thread_name, debug_thread.is_alive())
    pf_dbg_rdr.debug_port_reader()
    print('\nstopping {}'.format(thread_name))

def main():
    global L00P_thread, debug_thread
    pf_dbg_rdr.samurai_event = threading.Event()

    L00P_thread = threading.Thread(target=loop_thread, \
        args=('L00P_thread', pf_dbg_rdr.samurai_event))

    dld_img_thread = threading.Thread(target=image_dld, \
        args=('image_download', pf_dbg_rdr.samurai_event))

    debug_thread = threading.Thread(target=debug_port_thread, \
        args=('debug_port_reader', pf_dbg_rdr.samurai_event))

    L00P_thread.start()
    dld_img_thread.start()
    debug_thread.start()
    debug_thread.join()

if __name__ == '__main__':
    main()
    print('processes stopped')
    print "Exiting Main Thread"

Answer 1

在while条件中使用第二个变量，一旦达到超时，就可以更改。

例如：

shouldRun = True
while not thread_event.is_set() and shouldRun:
    print("value of loopCnt = {}".format(loopCnt))
    loopCnt += 1
    time.sleep(1)
    if loopCnt > 60: shouldRun = False

将在60次迭代后停止（大约60秒，每次迭代时你睡眠1秒钟。）

导致线程停留在while循环中时停止？

1 个答案: