client.py

##################### client ###########################
# sends a single one-line command

import socket
import time
import sys

# Create a UDS socket
sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)

# Connect the socket to the port where the server is listening
server_address = '/tmp/socket'
print('connecting to %s' % server_address)
try:
    sock.connect(server_address)
except socket.error as e:
    print(e)
    sys.exit(1)

f = sock.makefile('rwb', buffering=0)

try:
    # Send data
    print('sending command')
    # f.write(b'command1\n')
    f.write(b'command')
    raise Exception
    print(f.read())

finally:
    print('closing socket')
    f.close()
    sock.close()

server.py

##################################### server ###################################
# responds with a multiline string, then closes connection

import socket
import sys
import os

server_address = '/tmp/socket'

# Make sure the socket does not already exist
try:
    os.unlink(server_address)
except OSError:
    if os.path.exists(server_address):
        raise

# Create a UDS socket
sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)

# Bind the socket to the port
print('starting up on %s' % server_address)
sock.bind(server_address)

# Listen for incoming connections
sock.listen(1)


while True:
    # Wait for a connection
    print('waiting')
    connection, _ = sock.accept()
    f = connection.makefile('rwb', buffering=0)
    try:
        data = f.readline()
        print('received "%s"' % data)
        if data:
            f.write(b'this is the\nresponse to command 1')
            f.close()
        else:
            print('no more data from', client_address)

    except BrokenPipeError:
        print('client disconnected')
        connection.close()

    finally:
        # Clean up the connection
        connection.close()