class Daemons::Pid

def self.dir(dir_mode, dir, script)
  # nil script parameter is allowed as long as dir_mode is not :script
  return nil if dir_mode == :script && script.nil?
  case dir_mode
    when :normal
      return File.expand_path(dir)
    when :script
      return File.expand_path(File.join(File.dirname(script), dir))
    when :system
      return '/var/run'
    else
      fail Error.new("pid file mode '#{dir_mode}' not implemented")
  end
end

def self.running?(pid)
  return false unless pid
  # Check if process is in existence
  # The simplest way to do this is to send signal '0'
  # (which is a single system call) that doesn't actually
  # send a signal
  begin
    Process.kill(0, pid)
    return true
  rescue TimeoutError
    raise
  rescue Errno::ESRCH
    return false
  rescue ::Exception   # for example on EPERM (process exists but does not belong to us)
    return true
  end
end

def cleanup
end

def exist?
  true
end

def initialize
end

def pid
end

def pid=(p)
end

def running?
  Pid.running?(pid)
end

def zap
end