在Python上使用套接字进行通信

Question

I have made two scripts to practice using sockets in Python but I have trouble communicating after the connexion is established: My scripts below :

Server.py

#!/usr/local/bin/python3.5

import socket, sys

HOST = 'myIP'
PORT = 50000
counter = 0

mySocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

try:
    mySocket.bind((HOST,PORT))
except socket.error:
    print("Socket connection failed.")
    sys.exit

while 1:
    print("Server ready, waiting for request...")
    mySocket.listen(2)

    connexion, adress = mySocket.accept()
    counter+=1
    print("Client connected, adress IP %s, port %s" % (adress[0], adress[1]))

    msgServeur="Connected to server PytPyt. You can send messages."
    connexion.send(msgServeur.encode("Utf8"))
    msgClient = connexion.recv(1024).decode("Utf8")
    while 1:
        print("C>", msgClient)
        if msgClient.upper() == "END" or msgClient == "":
            break
        msgServeur = input("S> ")
        connexion.send(msgServeur.encode("Utf8"))
        msgClient = connexion.recv(1024).decode("Utf8")

    connexion.send("end".encode("Utf8"))
    print("Connexion finished.")
    connexion.close()

    ch=input("<R>etry <T>erminate?")
    if ch.upper() =='T':
        break

Client.py

#!/usr/local/bin/python3.5

import socket, sys

HOST = 'myIP'
PORT = 50000

mySocket=socket.socket(socket.AF_INET, socket.SOCK_STREAM)

try:
    mySocket.connect((HOST, PORT))
except socket.error:
    print("Connexion failed.")
    sys.exit()
print("Connexion established with server.")

msgServeur = mySocket.recv(1024).decode("Utf8")

while 1:
    if msgServeur.upper == "END"  or msgServeur == "":
        break
    print("S>", msgServeur)
    msgClient=input("C> ")
    mySocket.send(msgClient.encode("Utf8"))
    msgServeur = mySocket.recv(1024).decode("Utf8")

print("Connexion terminated.")
mySocket.close()

When I execute the two scripts I have the result below :

Server :

myPrompt : ./Server.py &
Server ready, waiting for request...
Client connected, adresse IP myIP, port 53551 

Client :

myPrompt : ./Client.py &
Connexion established with server.
S> Connected to server PytPyt. You can send messages.
C> hello
-bash: hello: command not found

[1]+  Stopped                 ./Client.py

It seems that my message is executed as a bash command and not a message to send. However if I run the job again it will work :

Client :

myPrompt : %
./Client.py
hello

Server :

C> hello
S> 

But it fails again right after. I have to run the job again any time I want to send a message.

Do you know where the mistake is?

Answer 1

Actually problem lay in script launching. You using following command

./Client.py &

With & the process starts in the background, so you can continue to use the shell. & detach stdin of your script from terminal. And all that you print in terminal after script launching will be interpreted as bash commands.
Try to use just

./Client.py