#include <stdio.h>
#include <unistd.h>

#include <sys/types.h>
#include <sys/stat.h>

int main(int argc, char *argv[])
{
	/*
	 * Funzione che mi crea un demone
	 */
	
	int pid;
	
	// create - fork 1
	if(fork()) return 0;

	// it separates the son from the father
	chdir("/");
	setsid();
	umask(0);

	// create - fork 2
	pid = fork();

	if(pid)
	{
		printf("Daemon: %d\n", pid);
		return 0;
	}
	
	/****** Codice da eseguire ********/	
	FILE *f;

	f=fopen("/tmp/coa.log", "w");
	
	while(1)
	{
		fprintf(f, "ciao\n");
		fflush(f);
		sleep(2);
	}
	/**********************************/
}

def createDaemon():
	'''Funzione che crea un demone per eseguire un determinato programma...'''
	
	import os
	
	# create - fork 1
	try:
		if os.fork() > 0: os._exit(0) # exit father...
	except OSError, error:
		print 'fork #1 failed: %d (%s)' % (error.errno, error.strerror)
		os._exit(1)

	# it separates the son from the father
	os.chdir('/')
	os.setsid()
	os.umask(0)

	# create - fork 2
	try:
		pid = os.fork()
		if pid > 0:
			print 'Daemon PID %d' % pid
			os._exit(0)
	except OSError, error:
		print 'fork #2 failed: %d (%s)' % (error.errno, error.strerror)
		os._exit(1)

	funzioneDemo() # function demo
	
def funzioneDemo():

	import time

	fd = open('/tmp/demone.log', 'w')
	while True:
		fd.write(time.ctime()+'\n')
		fd.flush()
		time.sleep(2)
	fd.close()
	
if __name__ == '__main__':

	createDaemon()