If you want to do it with code in python, this is a pretty standard C-method that was ported to python that I use. It works flawlessly, and you can even choose a file output.
import os
import signal
def daemonize(workingdir='.', umask=0,outfile='/dev/null'):
#Put in background
pid = os.fork()
if pid == 0:
#First child
os.setsid()
pid = os.fork() #fork again
if pid == 0:
os.chdir(workingdir)
os.umask(umask)
else:
os._exit(0)
else:
os._exit(0)
#Close all open resources
try:
os.close(0)
os.close(1)
os.close(2)
except:
raise Exception("Unable to close standard output. Try running with 'nodaemon'")
os._exit(1)
#Redirect output
os.open(outfile, os.O_RDWR | os.O_CREAT)
os.dup2(0,1)
os.dup2(0,2)
Then, you can use signals to catch when a kill-signal was sent to the program and exit nicely. Example from Python Docs
import signal, os
def handler(signum, frame):
print 'Signal handler called with signal', signum
raise IOError("Couldn't open device!")
# Set the signal handler and a 5-second alarm
signal.signal(signal.SIGALRM, handler)
signal.alarm(5)
# This open() may hang indefinitely
fd = os.open('/dev/ttyS0', os.O_RDWR)
signal.alarm(0) # Disable the alarm