Pyhton编程：socket实现ssh通讯

import socket
import os
server = socket.socket()
server.bind(("localhost", 6969)) # 绑定监听端口
server.listen(5)  # 监听
print("监听开始..")
while True:
    conn, addr = server.accept()  # 等待连接
    print("conn:", conn, "\naddr:", addr)  # conn连接实例
    while True:
        data = conn.recv(1024)  # 接收
        if not data:  # 客户端已断开
            print("客户端断开连接")
            break
        print("收到的命令：", data.decode("utf-8"))
        res = os.popen(data.decode("utf-8")).read()
        print("发送的大小：", len(res))
        conn.send(str(len(res)).encode("utf-8"))  # 先发送长度
        confirm = conn.recv(1024)  # 等待确认，解决粘包问题
        print(res)
        conn.send(res.encode("utf-8"))  # 再发送内容
server.close()

import socket
client = socket.socket()  # 生成socket连接对象
ip_port =("localhost", 6969)  # 地址和端口号
client.connect(ip_port)  # 连接
print("服务器已连接")
while True:
    content = input(">>")
    if len(content)==0: continue  # 如果传入空字符会阻塞
    client.send(content.encode("utf-8"))  # 传送和接收都是bytes类型
    receive_size = client.recv(1024)  # 先接收长度，建议8192
    data_size = int(receive_size.decode("utf-8"))
    print("接收到的大小：", data_size)
    client.send("准备好接收".encode("utf-8"))
    datas = ""
    while len(datas) < data_size:
        data = client.recv(1024)  # 多次接收内容，接收大数据
        datas += data.decode("utf-8")
    print(len(datas), datas)  # 解码
client.close()