socket_examples_README.md

This file is part of eRCaGuy_hello_world: https://github.com/ElectricRCAircraftGuy/eRCaGuy_hello_world

Socket examples & study

1. *****+ EXCELLENT example code, UDP sending and receiving examples, multicast, etc: https://wiki.python.org/moin/UdpCommunication
2. TCP example code: https://wiki.python.org/moin/TcpCommunication
3. https://docs.python.org/3/library/select.html#poll-objects - select — Waiting for I/O completion — Python 3.11.4 documentation [GS notes: how to do Ethernet polling in Python: create a socket, call poll.register(fd) to pass in the socket fd file descriptor, then call poll.poll([timeout_ms]) to get back an iterable tuple of (fd, event) 2-tuples telling me which socket file descriptors are ready to be read and have data right now!; how to do ethernet socket polling in Python--see my notes to the left!]

Examples

From: https://wiki.python.org/moin/UdpCommunication

1. UDP sender ("client"):

   import socket
   
   UDP_IP = "127.0.0.1"
   UDP_PORT = 5005
   MESSAGE = b"Hello, World!"
   
   print("UDP target IP: %s" % UDP_IP)
   print("UDP target port: %s" % UDP_PORT)
   print("message: %s" % MESSAGE)
   
   sock = socket.socket(socket.AF_INET, # Internet
                        socket.SOCK_DGRAM) # UDP
   sock.sendto(MESSAGE, (UDP_IP, UDP_PORT))

2. UDP receiver ("server")

   import socket
   
   UDP_IP = "127.0.0.1"
   UDP_PORT = 5005
   
   sock = socket.socket(socket.AF_INET, # Internet
                        socket.SOCK_DGRAM) # UDP
   sock.bind((UDP_IP, UDP_PORT))
   
   while True:
       data, addr = sock.recvfrom(1024) # buffer size is 1024 bytes
       print("received message: %s" % data)

From: https://wiki.python.org/moin/TcpCommunication

1. TCP sender ("client"): see link above.
2. TCP receiver ("server"): see link above.