Python3でのソケット同期通信の説明例

from socket import *
from time import ctime
HOST = ''
PORT = 21567
BUFSIZE = 1024
ADDR = (HOST, PORT)
tcpSerSock = socket(AF_INET, SOCK_STREAM)
tcpSerSock.bind(ADDR)
tcpSerSock.listen(5)
quit = False
shutdown = False
while True:
  print('waiting for connection...')
  tcpCliSock, addr = tcpSerSock.accept()
  print('...connected from: ', addr)
  while True:
    data = tcpCliSock.recv(BUFSIZE)
    data = data.decode('utf8')
    if not data:
      break
    ss = '[%s] %s' %(ctime(), data)
    tcpCliSock.send(ss.encode('utf8'))
    print(ss)
    if data == 'bye':
      quit = True
      break
    elif data == 'shutdown':
      shutdown = True
      break
  print('Bye-bye: [%s: %d]' %(addr[0], addr[1]))
  tcpCliSock.close()
  if shutdown:
    break
tcpSerSock.close()
print('Server has been

from socket import *
HOST = 'localhost'
PORT = 21567
BUFSIZE = 1024
ADDR = (HOST, PORT)
tcpCliSock = socket(AF_INET, SOCK_STREAM)
tcpCliSock.connect(ADDR)
while True:
  data = input('>')
  if not data:
    continue
  print('input data: [%s]' %data)
  tcpCliSock.send(data.encode('utf8'))
  rdata = tcpCliSock.recv(BUFSIZE)
  if not rdata:
    break
  print(rdata.decode('utf8'))
  if data == 'bye' or data == 'shutdown':
    break
tcpCliSock.close()