Linux Programming Interface 57.2 Stream Sockets in the UNIX Domain(in Python)

session.txt

$ python us_xfr_sv.py > b &
[1] 1553
$ cat *py > a
$ python us_xfr_cl.py  < a
$ kill %1
[1]+  Terminated              python us_xfr_sv.py > b
$ diff -u a b
$

us_xfr_cl.py

# The Linux Programming Interface Listing 57-4: A simple UNIX domain stream socket client
# Python port of sockets/us_xfr_cl.c
import socket
import sys

def main():
    sfd = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
    sv_sock_path  = '/tmp/us_xfr'

    try:
        sfd.connect(sv_sock_path)
    except socket.error:
        sys.exit('connect')

    while True:
        try:
            buff = raw_input()
        except EOFError:
            break
        try:
            sfd.send(buff + '\n')
        except socket.error:
            sys.exit('send')

if __name__ == '__main__':
    main()

us_xfr_sv.py

# The Linux Programming Interface Listing 57-3: A simple UNIX domain stream socket server
# Python port of sockets/us_xfr_sv.c
import os
import socket
import sys

BACKLOG = 5

def main():
    sfd = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
    sv_sock_path  = '/tmp/us_xfr'

    if os.path.exists(sv_sock_path):
        os.remove(sv_sock_path)

    try:
        sfd.bind(sv_sock_path)
    except socket.error:
        sys.exit('bind')

    try:
        sfd.listen(BACKLOG)
    except socket.error:
        sys.exit('listen')

    while True:
        cfd, addr = sfd.accept()
        while True:
            data = cfd.recv(1024)
            if not data:
                break
            sys.stdout.write(data)
            sys.stdout.flush()
        cfd.close()

if __name__ == '__main__':
    main()