instance method cache_get_multi

# File activesupport/lib/active_support/vendor/memcache-client-1.7.4/memcache.rb, line 740
  def cache_get_multi(server, cache_keys)
    with_socket_management(server) do |socket|
      values = {}
      socket.write "get #{cache_keys}\r\n"

      while keyline = socket.gets do
        return values if keyline == "END\r\n"
        raise_on_error_response! keyline

        unless keyline =~ /\AVALUE (.+) (.+) (.+)/ then
          server.close
          raise MemCacheError, "unexpected response #{keyline.inspect}"
        end

        key, data_length = $1, $3
        values[$1] = socket.read data_length.to_i
        socket.read(2) # "\r\n"
      end

      server.close
      raise MemCacheError, "lost connection to #{server.host}:#{server.port}" # TODO: retry here too
    end
  end