gistfile1.rb

#!/usr/bin/env ruby

# Daemon script for running ifs_notify
# The script can start, stop and check status of ifs_notify

pwd = Dir.getwd
file = pwd + "/ifs_notify"
pidfile = "../var/ifs_notify.pid"

# Starting ifs_notify
def start(pidfile, file)
  if File.exists? pidfile
    begin
      mypid = File.open(pidfile).readline
      proc_check = Process.kill(0, mypid.to_i) # check is process ID found in file is running
    rescue
      File.delete(pidfile) # pid was not found so delete the file and start the program
    end
    if proc_check == 1
      puts "ifs_notify already running as PID #{mypid}, ifs_notify will not start\n"
      exit 1
    end
  end

  pid = fork do
    puts "Starting ifs_notify with PID #$$\n"
    File.open("../var/ifs_notify.pid", 'w') {|f| f.write("#$$") }
    exec file
    sleep
  end
  Process.detach(pid)
end

# Checking status of ifs_notify --- Need to add part about check if socket is open copy from above
def status(pidfile)
  if File.exists? pidfile
    mypid = File.open(pidfile).readline
    puts "ifs_notify is running, process ID is #{mypid}\n"
  else
    puts "ifs_notify is not running\n"
  end
end

# Stopping ifs_notify
def stop(pidfile)
  if File.exists? pidfile
    mypid = File.open(pidfile).readline
    Process.kill("TERM", mypid.to_i)
    File.delete(pidfile)
    puts "ifs_notify running as PID #{mypid} has been shutdown\n"
  else
    puts "Cannot find pid for ifs_notify\n"
  end
end

# Parse through user cmdline input
if ARGV[0] == "start"
  start(pidfile, file)
elsif ARGV[0] == "status"
  status(pidfile)
elsif ARGV[0] == "stop"
  stop(pidfile)
else
  puts "Please select an option, choices are start|status|stop\n"
end