Chapter 5 ■ Network Data aND Network errors
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print('Listening at', sock.getsockname())
sc, sockname = sock.accept()
print('Accepted connection from', sockname)
sc.shutdown(socket.SHUT_WR)
message = b''
while True:
more = sc.recv(8192) # arbitrary value of 8k
if not more: # socket has closed when recv() returns ''
print('Received zero bytes - end of file')
break
print('Received {} bytes'.format(len(more)))
message += more
print('Message:\n')
print(message.decode('ascii'))
sc.close()
sock.close()
def client(address):
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(address)
sock.shutdown(socket.SHUT_RD)
sock.sendall(b'Beautiful is better than ugly.\n')
sock.sendall(b'Explicit is better than implicit.\n')
sock.sendall(b'Simple is better than complex.\n')
sock.close()
if name == 'main':
parser = ArgumentParser(description='Transmit & receive a data stream')
parser.add_argument('hostname', nargs='?', default='127.0.0.1',
help='IP address or hostname (default: %(default)s)')
parser.add_argument('-c', action='store_true', help='run as the client')
parser.add_argument('-p', type=int, metavar='port', default=1060,
help='TCP port number (default: %(default)s)')
args = parser.parse_args()
function = client if args.c else server
function((args.hostname, args.p))
If you run this script as a server and then, at another command prompt, run the client version, you will see that
all of the client’s data makes it intact to the server, with the end-of-file event generated by the client closing the socket
serving as the only framing that is necessary.
$ python streamer.py
Run this script in another window with "-c" to connect
Listening at ('127.0.0.1', 1060)
Accepted connection from ('127.0.0.1', 49057)
Received 96 bytes
Received zero bytes - end of file
Message:
Beautiful is better than ugly.
Explicit is better than implicit.
Simple is better than complex.