grub-editenv (GRUB) 2.02~beta2-36ubuntu3.7

Usage: grub-editenv [OPTION...] FILENAME COMMAND Tool to edit environment block. Commands: create Create a blank environment block file. list List the current variables. set [NAME=VALUE ...] Set variables. unset [NAME ...] Delete variables. -?, --help give this help list --usage give a short usage message -v, --verbose print verbose messages. -V, --version print program version Options: If FILENAME is `-', the default value /boot/grub/grubenv is used. There is no `delete' command; if you want to delete the whole environment block, use `rm /boot/grub/grubenv'. Report bugs to <bug-grub@gnu.org>.