day 30-3 练习

一：进程之间的内存空间是共享的还是隔离的？下述代码的执行结果是什么？

结果： 
主进程：100
子进程：0
进程之间的内存空间是隔离的。

from multiprocessing import Process

n=100 #在windows系统中应该把全局变量定义在if __name__ == '__main__'之上就可以了

def work():
    global n
    n=0
    print('子进程内: ',n)


if __name__ == '__main__':
    p=Process(target=work)
    p.start()
    p.join()
    print('主进程内: ',n)

 

二：基于多进程实现并发的套接字通信？

服务端

from socket import *
from multiprocessing import Process


class Server:
    code = 'utf-8'
    family_net = AF_INET
    type_net = SOCK_STREAM
    request_queue_size = 5
    max_packet_size = 1024

    def __init__(self, server_address):
        self.server_address = server_address
        self.socket = socket(self.family_net, self.type_net)

        try:
            self.server_bind()
            self.server_listen()
        except:
            self.server_close()
            raise

    def server_bind(self):
        self.socket.bind(self.server_address)

    def server_listen(self):
        self.socket.listen(self.request_queue_size)

    def server_close(self):
        self.socket.close()

    def run(self):
        while True:
            print('waiting...')
            self.conn, self.addr = self.socket.accept()
            p = Process(target=self.sub_p,)
            p.start()

    def sub_p(self):
        while True:
            ret = self.conn.recv(self.max_packet_size).decode(self.code)
            if not ret: break
            ret_bytes = ret.upper().encode(self.code)
            self.conn.send(ret_bytes)


if __name__ == '__main__':
    s = Server(('127.0.0.1', 8099))
    s.run()

客户端

from socket import *


class Client:
    code = 'utf-8'
    family_net = AF_INET
    type_net = SOCK_STREAM
    max_packet_size = 1024

    def __init__(self, server_address):
        self.server_address = server_address
        self.socket = socket(self.family_net, self.type_net)

        try:
            self.client_connect()
        except:
            self.clent_close()
            raise

    def client_connect(self):
        self.socket.connect(self.server_address)

    def clent_close(self):
        self.socket.close()

    def run(self):
        while 1:
            ret = input('>>>').strip()
            if not ret: break
            self.socket.send(ret.encode(self.code))
            data = self.socket.recv(self.max_packet_size)
            print(data.decode(self.code))

if __name__ == '__main__':
    c = Client(('127.0.0.1', 8099))
    c.run()