python——多线程thread

python通过thread模块支持多线程，语法也很简洁，现在通过一个实例来看一下python中的多线程：

import threadimport time#保证只额外启动一个线程isRunning=False#启动的时间控制，测试时间是23点44分，所以定的是这个时间，可以用于指定定时任务的执行时间timer_hour=23timer_min=44#额外其他一个线程处理任务def another_thread():    print '[another_thread] is start...'    #声明使用全局变量isRunning    global isRunning    #for循环模拟任务执行    for i in range(3):        time.sleep(1)        print '[another_thread] time: %s ' % time.strftime('%Y-%m-%d %X',time.localtime())        print '[another_thread] Is Running: %s' % isRunning    #此处只是为了保证该任务一天只启动一次，一分不会超过60秒    time.sleep(60)    print '[another_thread] is end...'    #该状态只是为了保证该任务不会重复启动，当然对于任务可以设置一个超时时间，到时不结束自动终结    isRunning = Falseif __name__ == '__main__':    while True:        now = time.localtime()        print '[main_thread] time: %s' % time.strftime('%Y-%m-%d %X',now)        print '[main_thread] Is Running: %s' % isRunning        if now.tm_hour==timer_hour and now.tm_min==timer_min and not isRunning:            #进入任务前即置为True状态，防止重复启动            isRunning = True            #python开启一个新的线程，从后面打印日志的情况可以知道，并不会影响主线程的运行            thread.start_new_thread(another_thread,())                 time.sleep(1)

代码执行后如下：

C:\Users\Captain\Desktop>python task.py[main_thread] time: 2013-07-31 23:44:56[main_thread] Is Running: False[another_thread] is start...[main_thread] time: 2013-07-31 23:44:57[another_thread] time: 2013-07-31 23:44:57[main_thread] Is Running: True[another_thread] Is Running: True[main_thread] time: 2013-07-31 23:44:58[another_thread] time: 2013-07-31 23:44:58[main_thread] Is Running: True[another_thread] Is Running: True[main_thread] time: 2013-07-31 23:44:59[another_thread] time: 2013-07-31 23:44:59[another_thread] Is Running: True[main_thread] Is Running: True[main_thread] time: 2013-07-31 23:45:00[main_thread] Is Running: True[main_thread] time: 2013-07-31 23:45:01[main_thread] Is Running: True[main_thread] time: 2013-07-31 23:45:02

该实例很简单，可按照这个思路，应用于定时任务，心跳检测，守护进程等实际场景中