server.py

import socket
import os

server = socket.socket()
server.bind(('localhost',8080))
server.listen()

while True:
    conn,addr = server.accept()#默认堵塞,生成conn实例
    print('new connect:',addr)

    while True:
        cmd = conn.recv(1024)#默认堵塞,如果客户端断开，将收到空数据
        if not cmd:
            print('the client has lost!!!')
            break
        else:
            print('the command is ',cmd.decode())
        cmd_res = os.popen(cmd.decode()).read()
        if not cmd_res:
            cmd_res = '无效指令'
        conn.send(cmd_res.encode())


server.close()

client.py

import socket

client = socket.socket()
client.connect(('localhost',8080))

while True:
    data = input('>>>').strip()
    if not data:
        continue
    client.send(data.encode())
    data = client.recv(1024)
    print(data.decode())

client.close()

当服务端返回数据的大小大于客户端接受最大值，接收数据将会出现异常。可以通过客户端循环接受代码解决

client.py

import socket

client = socket.socket()
client.connect(('10.10.10.131',8080))

while True:
    data = input('>>>').strip()
    if not data:
        continue
    client.send(data.encode())
    data = client.recv(1024)
    data_size = int(data)
    print('the size is ',data_size)
    receive_size = b''

    while len(receive_size) < data_size:
        receive_size += client.recv(1024)
    else:
        print('received size is ',len(receive_size))
        print(receive_size.decode())
    

client.close()

server.py

import socket
import os

server = socket.socket()
server.bind(('0.0.0.0',8080))
server.listen()

while True:
    conn,addr = server.accept()#默认堵塞,生成conn实例
    print('new connect:',addr)

    while True:
        cmd = conn.recv(1024)#默认堵塞,如果客户端断开，将收到空数据
        if not cmd:
            print('the client has lost!!!')
            break
        else:
            print('the command is ',cmd.decode())
        cmd_res = os.popen(cmd.decode()).read()
        if not cmd_res:
            cmd_res = '无效指令'
        conn.send(str(len(cmd_res)).encode())
        conn.sendall(cmd_res.encode())



server.close()