python 线程模块创建线程

#Python 多线程示例。
#1. 使用递归计算阶乘。
#2. 使用线程调用阶乘函数。
 
from _thread import start_new_thread
from time import sleep
 
threadId = 1 #线程计数器
waiting = 2 #2秒等待的时间
 
def factorial(n):
    global threadId
    rc = 0
    
    if n < 1:   # base case
        print("{}: {}".format('\nThread', threadId ))
        threadId += 1
        rc = 1
    else:
        returnNumber = n * factorial( n - 1 )  # recursive call
        print("{} != {}".format(str(n), str(returnNumber)))
        rc = returnNumber
    
    return rc
 
start_new_thread(factorial, (5, ))
start_new_thread(factorial, (4, ))
 
print("Waiting for threads to return...")
sleep(waiting)