python3 tcp的粘包现象和解决办法

Posted 2020-11-24 lilyxiaoyy

服务器端

import socket

sk = socket.socket()
sk.bind(("127.0.0.1", 6666))
sk.listen()
conn, address = sk.accept()


def my_send(msg):
    bs = msg.encode("utf-8")
    len_str = format(len(bs), "04d")  # 定长4位
    conn.send(len_str.encode("utf-8"))
    conn.send(bs)


my_send(input(">>>:").strip())
my_send(input(">>>:").strip())

 

客户端

import socket
import time

sk = socket.socket()
sk.connect(("127.0.0.1", 6666))

time.sleep(10)  # 制造粘包情况
msg = sk.recv(1024).decode("utf-8")  # 粘包现象
print(msg)

执行结果：

0004aaaa0003bbb

有粘包的现象。

 

解决粘包，客户端代码调整

import socket
import time

sk = socket.socket()
sk.connect(("127.0.0.1", 6666))
time.sleep(10)

def my_recv():
    len_str = int(sk.recv(4).decode("utf-8"))
    msg = sk.recv(len_str)
    print(f"来自服务端的消息：{msg.decode(‘utf-8‘)}")


my_recv()
my_recv()

执行结果：

来自服务端的消息：aaaa
来自服务端的消息：bbb