Creating a daemon process in Python

Hi,

What is the easiest way to create a daemon process in Python? Google
says I should call fork() and other system calls manually, but is
there no os.daemon() and the like?

Regards,

--
Sakagami Hiroki

re: Creating a daemon process in Python

Hello,

Sakagami Hiroki wrote:
You could try
<http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/278731>


HTH

--
Benjamin Niemann
Email: pink at odahoda dot de
WWW: http://pink.odahoda.de/

re: Creating a daemon process in Python

Sakagami Hiroki wrote:I find that this works great. I just pasted my copy, I think you can
find it via Google.

Eirikur


# Daemon Module - basic facilities for becoming a daemon process
# By Coy Krill
# Combines ideas from Steinar Knutsens daemonize.py and
# Jeff Kunces demonize.py

"""Facilities for Creating Python Daemons"""

import os
import time
import sys

class NullDevice:
def write(self, s):
pass

def daemonize():
if (not os.fork()):
# get our own session and fixup std[in,out,err]
os.setsid()
sys.stdin.close()
sys.stdout = NullDevice()
sys.stderr = NullDevice()
if (not os.fork()):
# hang around till adopted by init
ppid = os.getppid()
while (ppid != 1):
time.sleep(0.5)
ppid = os.getppid()
else:
# time for child to die
os._exit(0)
else:
# wait for child to die and then bail
os.wait()
sys.exit()

re: Creating a daemon process in Python

On Feb 21, 9:33 am, Eirikur Hallgrimsson <e...@mad.scientist.com>
wrote:I've found it even easier to use the built in threading modules:

import time

t1 = time.time()
print "t_poc.py called at", t1

import threading

def im_a_thread():
time.sleep(10)
print "This is your thread speaking at", time.time()

thread = threading.Thread(target=im_a_thread)
thread.setDaemon(True)
thread.start()
t2 = time.time()
print "Time elapsed in main thread:", t2 - t1


Of course, your mileage may vary.

re: Creating a daemon process in Python

garrickp@gmail.com wrote:
That's not a daemon process (which are used to execute 'background services'
in UNIX environments).

--
Benjamin Niemann
Email: pink at odahoda dot de
WWW: http://pink.odahoda.de/

re: Creating a daemon process in Python

On Feb 21, 3:34 pm, Benjamin Niemann <p...@odahoda.dewrote:I had not tested this by running the script directly, and in writing a
response, I found out that the entire interpreter closed when the main
thread exited (killing the daemonic thread in the process). This is
different behavior from running the script interactively, and thus my
confusion.

Thanks! ~Garrick

re: Creating a daemon process in Python

Thanks all,

I understood there is no shortcut function like BSD daemon(). I'll do
it manually using examples from cookbook...



On 2$B7n(B22$BF|(B, $B8aA0(B1:41, Benjamin Niemann <p...@odahoda.dewrote:

re: Creating a daemon process in Python

On 2007-02-22, okahashi@gmail.com <okahashi@gmail.comwrote:
Sure would be nice if somebody posted one. ;)

--
Grant Edwards grante Yow! Oh, I get it!! "The
at BEACH goes on", huh,
visi.com SONNY??

re: Creating a daemon process in Python

Benjamin Niemann wrote:
Also, more discussion on the topic here:
http://aspn.activestate.com/ASPN/Coo...n/Recipe/66012

j

--
Joshua Kugler
Lead System Admin -- Senior Programmer
http://www.eeinternet.com
PGP Key: http://pgp.mit.edu/ Â*ID 0xDB26D7CE

--
Posted via a free Usenet account from http://www.teranews.com

re: Creating a daemon process in Python

Eirikur Hallgrimsson <eh@mad.scientist.comwrote:That doesn't close the underlying file descriptors...

Here is another method which does :-

null = os.open(os.devnull, os.O_RDWR)
os.dup2(null, sys.stdin.fileno())
os.dup2(null, sys.stdout.fileno())
os.dup2(null, sys.stderr.fileno())
os.close(null)

Why do you need hang around until adopted by init? I've never see
that in a daemonize recipe before?
--
Nick Craig-Wood <nick@craig-wood.com-- http://www.craig-wood.com/nick