grub: chainloader

 
 16.3.10 chainloader
 -------------------
 
  -- Command: chainloader [--force] file
      Load FILE as a chain-loader.  Like any other file loaded by the
      list syntax::) to grab the first sector of the current partition
      with '+1'.  If you specify the option '--force', then load FILE
      forcibly, whether it has a correct signature or not.  This is
      required when you want to load a defective boot loader, such as SCO
      UnixWare 7.1.