网络编程

一、协程介绍及基本示例

      手动切换（greenlet)

from greenlet import greenlet

def test1():
    print (12)
    gr2.switch()
    print(34)
    gr2.switch()
    print (90)

def test2():
    print (56)
    gr1.switch()
    print(78)
    gr1.switch()

gr1 = greenlet(test1)
gr2 = greenlet(test2)
gr1.switch()
首先切换到test1函数，遇到再切换时，会回到上一次切换停止的位置；运行结果为：

12
56
34
78
90