python 监听 其他程序发消息_python进程之间消息监控程序

外界调用向mgr进程发送消息，mgr根据不同消息启动或关闭相应进程(启动的进程，独占用，只启动一个)；

若有进程程退出 则mgr向外界发出信号。

外界代码：

#!/usr/bin/python

#

# -*- coding:utf-8 -*-

#

#

import sys

import os

import subprocess

import signal

import time

import random

def sig_usr1(signum, frame):

print("recive sinal from process(exited)")

signal.signal(signal.SIGUSR1, sig_usr1)

cmds= ['./mgr.py']

n =1

p = subprocess.Popen( cmds,stdin=subprocess.PIPE,stderr=subprocess.PIPE,close_fds=False)

while True:

time.sleep(1)

ret = p.poll()

if ret is None:

#print("main="+str(n))

p.stdin.write(str(n)+"\n")

p.stdin.flush()

p.send_signal(signal.SIGUSR1)

n = random.randint(1, 3)

print("main exit")

管理进程

#!/usr/bin/python

#

# -*- coding:utf-8 -*-

#

import sys

import os

import time

import signal

import subprocess

import json

data = {'num': 0, 'error': 0}

def getParentID():

p=subprocess.Popen("ps -ef|grep tt.py|grep -v grep|awk '{print $2}'",stdout=subprocess.PIPE,shell=True)

ret = int(p.stdout.readline())

return ret

par_id = getParentID()

print(par_id)

exe_process = 0

isRuning = True

def sig_usr1(signum, frame):

ret = sys.stdin.readline()

data['num'] = int(ret)

signal.signal(signal.SIGUSR1, sig_usr1)

while isRuning:

time.sleep(1)

print("data['num'] ="+str(data['num']))

if exe_process == 0: #for open

if data['num'] == 1:

exe_process=subprocess.Popen("./a.out",close_fds=False)

elif data['num'] == 2:

exe_process=subprocess.Popen("./b.out",close_fds=False)

else:

continue

else: #if exe_process == 0: for close

ret = exe_process.poll()

if ret is None:

if data['num'] == 3:

exe_process.terminate()

exe_process = 0

os.kill(par_id,signal.SIGUSR1)

else: #if ret is None self close

exe_process = 0

print("end"+str(par_id))

os.kill(par_id,signal.SIGUSR1)

print "mgr process over "

python进程通讯注意问题

1)发送信号： os.kill(par_id,signal.SIGUSR1)  #注意要 import os

2)subprocess结合管道要注意，不用就不要打开，否则容易出错

比如p = subprocess.Popen(cmd,stdin=subprocess.PIPE,close_fds=False)

stdin 要用到。

3)用subprocess调用Popen时候，cmd若是python脚本，要确保能编译通过并运行。则调用，否则不好排除错误