def read_pid
      content = {}
      if exists?
        open(@pid_file,'r') { |f| content[:pid] = f.read.to_i }
        open(@cookie_file,'r') do |f|
          command_options = (YAML.load(f.read) rescue {}) || {}
          content.merge!(command_options)
        end if File.readable?(@cookie_file)
      end
      content
    end
def read_pid
      content = {}
      if exists?
        open(@pid_file,'r') { |f| content[:pid] = f.read.to_i }
        open(@cookie_file,'r') do |f|
          command_options = (YAML.load(f.read) rescue {}) || {}
          content.merge!(command_options)
        end if File.readable?(@cookie_file)
      end
      content
    end
Read pid file content
 Empty hash if pid file does not exist or content cannot be loaded

 === Return
 content(Hash):: Hash containing 3 keys :pid, :cookie and :port