How to add a python program to run on startup the cli way

To make a python program run on startup..first create o file on /etc/init.d..am creating a file named timestamp.

touch /etc/init.d/timestamp

Now edit the file

vim  /etc/init.d/timestamp

and enter the following

#! /bin/bash
# Copyright (c) 1996-2012 My Company.
# All rights reserved.
#
# Author: Ganesh H, 2013
#
# Please send feedback to ganeshredcobra@gmail.com
#
# /etc/init.d/timestamp
#
### BEGIN INIT INFO
# Provides: timestamp
# Required-Start: 
# Should-Start: 
# Required-Stop: 
# Should-Stop:
# Default-Start:  2 3 4 5
# Default-Stop:   0 1 6
# Short-Description: Test daemon process
# Description:    Runs up the test daemon process
### END INIT INFO

# Activate the python virtual environment
#    . /path_to_virtualenv/activate

case "$1" in
  start)
    echo "Starting server"
    # Start the daemon 
    /usr/bin/python /home/ganesh/Pictures/timestamp.py start
    ;;
  stop)
    echo "Stopping server"
    # Stop the daemon
    /usr/bin/python /home/ganesh/Pictures/timestamp.py stop
    ;;
  restart)
    echo "Restarting server"
    /usr/bin/python /home/ganesh/Pictures/timestamp.py restart
    ;;
  *)
    # Refuse to do other stuff
    echo "Usage: /etc/init.d/timestamph {start|stop|restart}"
    exit 1
    ;;
esac

exit 0

give the correct path of the file..Now make the init.d file executable

chmod +x /etc/init.d/timestamp

Now add the script to bootup

sudo update-rc.d timestamp  defaults

or you can use chkconfig

chkconfig --add timestamp

To remove the startup

rm -fv /etc/rc*/*timestamp

or

chkconfig --del timestamp

To view all configured startup use the below command

chkconfig --list

Happy Hacking 🙂

How to make a python program run as daemon

To make a python program run as daemon process use the following program..

#! /usr/bin/env python
# -*- coding: utf-8 -*-
#
#       Copyright 2013 ganesh #ganeshredcobra@gmail.com#
#
#       This program is free software; you can redistribute it and/or modify
#       it under the terms of the GNU General Public License as published by
#       the Free Software Foundation; either version 2 of the License, or
#       (at your option) any later version.
#
#       This program is distributed in the hope that it will be useful,
#       but WITHOUT ANY WARRANTY; without even the implied warranty of
#       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#       GNU General Public License for more details.
#
#       You should have received a copy of the GNU General Public License
#       along with this program; if not, write to the Free Software
#       Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
#       MA 02110-1301, USA.

from os import fork, chdir, setsid, umask
from sys import exit
import serial,os
import time
import syslog


def main():
    port = "/dev/ttyUSB0"
    ser = serial.Serial(port, 9600, timeout=0)
    last_received = ''
    buffer = ''
    while 1:
        #main daemon process loop
        

# Dual fork hack to make process run as a daemon
if __name__ == "__main__":
      try:
        pid = fork()
        if pid > 0:
          exit(0)
      except OSError, e:
        exit(1)

      chdir("/")
      setsid()
      umask(0)

      try:
        pid = fork()
        if pid > 0:
          exit(0)
      except OSError, e:
        exit(1)
main()

Put the program you want to daemonize inside the main function…now just run the program the process in main function will become daemon process..

to test the above program modify main function like this

def main():
     syslog.syslog('event occured')
     time.sleep(10)

Now run the program it becomes daemon and to check that

sudo tail -f  /var/log/syslog

you can see it will print “event occured” every ten seconds…

Happy hacking 🙂