59 lines
1.9 KiB
Python
59 lines
1.9 KiB
Python
import os
|
|
import sys
|
|
|
|
if os.name == 'posix':
|
|
def become_daemon(our_home_dir='.', out_log='/dev/null',
|
|
err_log='/dev/null', umask=022):
|
|
"Robustly turn into a UNIX daemon, running in our_home_dir."
|
|
# First fork
|
|
try:
|
|
if os.fork() > 0:
|
|
sys.exit(0) # kill off parent
|
|
except OSError, e:
|
|
sys.stderr.write("fork #1 failed: (%d) %s\n" % (e.errno, e.strerror))
|
|
sys.exit(1)
|
|
os.setsid()
|
|
os.chdir(our_home_dir)
|
|
os.umask(umask)
|
|
|
|
# Second fork
|
|
try:
|
|
if os.fork() > 0:
|
|
os._exit(0)
|
|
except OSError, e:
|
|
sys.stderr.write("fork #2 failed: (%d) %s\n" % (e.errno, e.strerror))
|
|
os._exit(1)
|
|
|
|
si = open('/dev/null', 'r')
|
|
so = open(out_log, 'a+', 0)
|
|
se = open(err_log, 'a+', 0)
|
|
os.dup2(si.fileno(), sys.stdin.fileno())
|
|
os.dup2(so.fileno(), sys.stdout.fileno())
|
|
os.dup2(se.fileno(), sys.stderr.fileno())
|
|
# Set custom file descriptors so that they get proper buffering.
|
|
sys.stdout, sys.stderr = so, se
|
|
else:
|
|
def become_daemon(our_home_dir='.', out_log=None, err_log=None, umask=022):
|
|
"""
|
|
If we're not running under a POSIX system, just simulate the daemon
|
|
mode by doing redirections and directory changing.
|
|
"""
|
|
os.chdir(our_home_dir)
|
|
os.umask(umask)
|
|
sys.stdin.close()
|
|
sys.stdout.close()
|
|
sys.stderr.close()
|
|
if err_log:
|
|
sys.stderr = open(err_log, 'a', 0)
|
|
else:
|
|
sys.stderr = NullDevice()
|
|
if out_log:
|
|
sys.stdout = open(out_log, 'a', 0)
|
|
else:
|
|
sys.stdout = NullDevice()
|
|
|
|
class NullDevice:
|
|
"A writeable object that writes to nowhere -- like /dev/null."
|
|
def write(self, s):
|
|
pass
|