grub: prefix

 
 15.1.36 prefix
 --------------
 
 The location of the '/boot/grub' directory as an absolute file name
 (⇒File name syntax).  This is normally set by GRUB at startup
 based on information provided by 'grub-install'.  GRUB modules are
 dynamically loaded from this directory, so it must be set correctly in
 order for many parts of GRUB to work.