Debugging with echo over socket

[abitrolly]

1. Open local socket to listen to incoming echoes.

$ nc -Ulk /tmp/socket
# -U  - open unix socket
# -l  - open for listening
# -k  - keep open for multiple connections

2. Add echo function to Python code

import socket
conn = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
conn.connect('/tmp/socket')
# ^ this will fail if nobody is listening on Unix socket

def echo(msg):
    conn.sendall(msg + '\n')
echo('--- start ---')
echo(sys.executable)

[abitrolly]

Error for conn.connect on Unix socket.

• socket.error: [Errno 111] Connection refused - socket file exists, but nobody listening
• socket.error: [Errno 2] No such file or directory - socket file doesn't exist