进程

进程间通信

 -*- coding:utf-8 -
import os
from multiprocessing import Queue

from multiprocessing import Process


def sub_message(q):
    while True:
        print(q.get())


def add_message(q):
    for i in range(5):
        q.put(i)
        print("%s添加了消息%s" % (os.getpid(), i))


def main():
    # 创建通信实例
    q = Queue(3) # 括号内不写即可以接受不限条数消息
    # 测一测现在q中的信息数
    print(q.qsize())
    # 创建2个进程实现通信
    pid1 = Process(target=add_message, args=(q,))
    pid2 = Process(target=sub_message, args=(q,))
    # 让进程开始
    pid1.start()
    pid2.start()
    # 等待进程执行任务完毕
    pid1.join()
    pid2.join()


if __name__ == "__main__":
    main()

进程池间通信

# -*- coding:utf-8 -*-
import os
from multiprocessing import Queue
from multiprocessing.pool import Pool

from multiprocessing import Manager

import time


def write(q, num):
    for temp in ["hello", "world", "python", "-end-"]:
        q.put(temp)
        print("任务%d,进程为%s,,添加了%s" % (num, os.getpid(), temp))
        time.sleep(1)


def read(q, num):
    while True:
        msg = q.get()
        if msg == "-end-":
            print("获取信息即将结束")
            break
        print("任务%d,进程%s获得了信息%s" % (num, os.getpid(), msg))
        time.sleep(1)


def main():
    q = Manager().Queue(5)  # Queue队列通信只能在继承的类间实现通信,对象池应用Manage()
    print(q.qsize())
    po = Pool(4)
    # 给进程池中进程添加任务
    for i in range(3):
        po.apply_async(write, args=(q, i))  # 用堵塞,先添加写入消息,再read
        po.apply_async(read, args=(q, i))
    # 关闭对象池
    po.close()
    # 等待执行完毕
    po.join()

if __name__ == "__main__":
    main()