Could someone explain how a python daemon can also function to communicate with a running instance of itself?

Question

I'd like to implement a Python module that functions as a daemon and as an interface to that daemon. For example, when I run:

python daemon.py do_something

The daemon module should try to communicate to the daemon to do_something , and if it doesn't exist, start the daemon and then do_something .

NOTE: I'd prefer to utilise the daemon package in Python 3.

Answer 1

On POSIX-compliant systems it is possible to pass the process arbitrary data locally with unix domain sockets. You can create both client and server socket using socket module . Parsing command line options (for example, using optparse or argparse modules) you can decide whether the daemon should be started or client socket connection opened to pass the command.