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Contents:
  1. Creating Daemons
    1. Using the multi-process module
    2. Using the Threading Module
    3. References
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Creating Daemons

There are three known ways to configure a task to run in the background; you can configure a shell script, use the threading module, and use the multi-process module.

Using the multi-process module

def proc_daemonize():
    mp.set_start_method('spawn')
    the_daemon = mp.Process(target=start_process, args=(), name='daemon', daemon=True)
    daemon = False
    if daemon:
        log.info('Daemonizing & sending to background...')
        the_daemon.start()
        the_daemon.join()
    else:
        log.info('Running in foreground...')
        exit(0)

Using the Threading Module

From Super Fast Python

# SuperFastPython.com
# example of a long-running daemon thread
from time import sleep
from random import random
from threading import Thread
 
# long-running background task
def background_task():
    global data
    # record the last seen value
    last_seen = data
    # run forever
    while True:
        # check for change
        if data != last_seen:
            # report the change
            print(f'Monitor: data has changed to {data}')
            # update last seen
            last_seen = data
        # block for a while
        sleep(0.1)
 
# global data
data =  0
# create and start the daemon thread
print('Starting background task...')
daemon = Thread(target=background_task, daemon=True, name='Monitor')
daemon.start()
# main thread is carrying on...
print('Main thread is carrying on...')
for _ in range(5):
    # block for a while
    value = random() * 5
    sleep(value)
    # update the data variable
    data = value
print('Main thread done.')

References