multi-process-logging.py

import os
import logging
from math import sqrt


def generate_primes(number):
    logger = logging.getLogger(str(os.getpid()) + ':logger')

    for num in range(number + 1):
       # prime numbers are greater than 1
       if num > 1:
           for i in range(2,int(sqrt(num)+1)):
               if (num % i) == 0:
                   break
           else:
               logger.info(num)

def start_workers():
    logger = logging.getLogger('parent:prime')
    logger.info('parent forking')

    for child in range(10):
        pid = os.fork()

        if pid == 0:
            logger = logging.getLogger(str(os.getpid()) + ':logger')
            fh = logging.FileHandler('logs/child_primes_' + str(os.getpid()) + '.log')

            logger.addHandler(fh)
            generate_primes(1000000)

            os._exit(0)


if __name__ == "__main__":

    logging.basicConfig(filename='logs/parent_primes.log', level=logging.INFO)
    logger = logging.getLogger('parent:prime')

    logger.info('Fork parent/child logging example.')
    logger.info('Starting children')

    start_workers()