def ensure_state_dir(daemon_dir)
    if not File.directory? daemon_dir then
      begin
        Dir.mkdir(daemon_dir)
      rescue Exception => ex
        $stderr.puts "Failed to create state dir: #{daemon_dir}; message:\n" + ex.message
        exit 1
      end
    end
    if not File.writable? daemon_dir then
      $stderr.puts "State dir is not writable: #{daemon_dir}"
      exit 1
    end
  end
def ensure_state_dir(daemon_dir)
    if not File.directory? daemon_dir then
      begin
        Dir.mkdir(daemon_dir)
      rescue Exception => ex
        $stderr.puts "Failed to create state dir: #{daemon_dir}; message:\n" + ex.message
        exit 1
      end
    end
    if not File.writable? daemon_dir then
      $stderr.puts "State dir is not writable: #{daemon_dir}"
      exit 1
    end
  end
Ensure that the var dir exists and is writable

 @raise [SystemExit] on error