网络编程之黏包

服务端:
import socket,struct,subprocess
server = socket.socket()
IPPORT = ('192.168.191.1',8008)
server.bind(IPPORT)
server.listen(5)
while 1:
    print('loading...')
    conn,addr = server.accept()
    print('%s已连接'%addr[0])
    while 1:
        cmd = conn.recv(1024).decode('utf8')
        print('收到了指令')
        res = subprocess.Popen(cmd,
                               shell=True,
                               stderr=subprocess.PIPE,
                               stdout=subprocess.PIPE
        )
        out = res.stdout.read()
        err = res.stderr.read()
        print("out响应长度", len(out))
        print("err响应长度", len(err))
        if err:
            message = err
        else:
            message = out
        conn.send(struct.pack("i", len(message)))
        conn.send(message)
客户端:

import socket,struct,subprocess,hashlib
client = socket.socket()
client.connect(('192.168.191.1',8008))
while 1:
    user_input = input("请输入指令>>>")
    client.send(user_input.encode('utf8'))
    head_data_length = struct.unpack('i',client.recv(4))[0]
    data_length = 0
    data=b""
    while data_length<head_data_length:
        recv_data = client.recv(1024)
        data +=recv_data
        data_length += len(recv_data)
    print(data.decode('gbk'))