python写进程_python写的daemon进程

import sys, os, time, atexit

from signal import SIGTERM

import signal

import subprocess

class Daemon:

def __init__(self, stdin='/dev/null', stdout='/home/workspace/py_server/engine.log', stderr='/dev/null'):

self.stdin = stdin

self.stdout = stdout

self.stderr = stderr

self.child_map = {}

def _daemonize(self):

pid = os.fork()

if (pid > 0):

sys.exit(0)

os.setsid()

os.chdir('/')

os.umask(0)

sys.stdout.flush()

sys.stderr.flush()

fd0 = file(self.stdin, 'r')

fd1 = file(self.stdout, 'a+')

fd2 = file(self.stderr, 'a+', 0)

os.dup2(fd0.fileno(), sys.stdin.fileno())

os.dup2(fd1.fileno(), sys.stdout.fileno())

os.dup2(fd2.fileno(), sys.stderr.fileno())

def start(self):

self._daemonize()

signal.signal(signal.SIGCHLD, self._handle_exit)

self._run()

def _run(self):

pass

def add_child(self, pid, cmd):

for pid_,cmd_ in self.child_map.items():

if cmd_ == cmd:del(self.child_map[pid_])

self.child_map[pid] = cmd

def register_signal(self, signal_num):

signal.signal(signal_num, self.handle_signal)

def _handle_exit(self, signal_num, arg):

pid, state = os.wait()

self.handle_exit(pid, state)

def handle_exit(self, pid, state):

pass

def handle_signal(self, signal_num, arg):

pass

def spawn_child(self, cmd):

process = subprocess.Popen(cmd, shell=True)

self.add_child(process.pid, cmd)写一个数继承Daemon类，重写_run方法，在里面写你的程序体，重写handle_exit方法，子进程退出时可以回调获得退出子进程的ID和退出状态，spawn_child传入字符串命令行，启动子进程。