Multithread Socket Programming in Python

Python Methods and Functions

Socket Programming - & gt; This helps us connect the client to the server. Client — the sender and recipient of the message, and the server — just a listener that works on the data sent by the client.

What is a theme?
Stream — it is a lightweight process that does not require a lot of memory and is less expensive than processes.

What is multithreaded socket programming?
Multithreading — it is the process of concurrent execution of multiple threads in one process.

Multithreaded modules:
_Thread module & amp; threading module used for multithreading in python, these modules help in synchronization and ensure that the thread is being used.

 from _thread import * import threading 

The lock object is created- & gt;

 print_lock = threading.Lock () 

A lock has two states: "locked" or "unlocked". It has two main methods acqu () and release (). When the state is unlocked, print_lock.acquire () is used to change the state to locked, and print_lock.release () is used to change the state to unlock.

Function thread.start_new_thread () is used to start a new thread and return its ID. The first argument — this is the called function, and the second — a tuple containing a positional list of arguments.

Let's learn programming client-server multithreaded sockets with
Note: -The code works with python3.

Multithreaded server-side code

# import socket programming library

import socket

# import thread module

from _ thread import *

import threading


print_lock = threading.Lock ()

# stream function

def threaded (c):

while True :


# data received from the client

data = c.recv ( 1024 )

if not data:

print ( 'Bye' )


  # unlocked on exit

print_lock.release ()



  # discard the given string from the client

data = data [:: - 1 ]


# send back string back to client

c.send (data)


  # closed

c.close ()



def Main ():

host = ""


# change the port on your computer

# in our case it is 12345 but this is

# can be anything

port = 12345

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

s.bind ((host, port))

print ( "socket binded to port" , port)


# put socket in listening mode

s.listen ( 5 )

print ( "socket is listening" )

  # forever loop until the client wants to exit

  while True :


# contact customer

c, addr = s.accept ()


# the lock received by the client

  print_lock.acquire ()

print ( 'Connected to:' , addr [ 0 ], ':' , addr [ 1 ])


# Start a new stream and return its ID

start_new_thread (threaded, (c,))

  s.close ()



if __ name__ = = '__main__' :

Main ()

 Console Window: socket binded to port 123 45 socket is listening Connected to: 11600 Bye 

Client Code

# Import the module socket

import socket



def Main ():

# local host IP & # 39; & # 39;

host = ''


# Determine the port you want to connect to

  port = 12345


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


# connect to the server on the local computer

s.connect ((host, port))


# the message you are sending to the server

message = "shaurya says pythonengineering"

while True :


# message sent to server

  s.send (message.encode ( 'ascii' ))


# message received from server

data = s.recv ( 1024 )


# print the received message

# postback will be here


print ( 'Received from the server:' , str (data.decode ( 'ascii' )))


# ask client if he wants to continue

ans = input ( 'Do you want to continue (y / n):' )

if ans = = 'y' :


else :


# close connection

  s.close ()


if __ name__ = = '__main__' :

  Main ()

 Console Window: Received from the server: skeegrofskeeg syas ayruahs Do you want to continue (y / n): y Received from the server: skeegrofskeeg syas ayruahs Do you want to continue (y / n ): n Process finished with exit code 0 

Reference & gt;

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