grub-set-default(8) [linux man page]
GRUB-SET-DEFAULT(8) System Administration Utilities GRUB-SET-DEFAULT(8) NAME
grub-set-default - set the saved default boot entry for GRUB SYNOPSIS
grub-set-default [OPTION] entry DESCRIPTION
Set the default boot entry for GRUB. -h, --help print this message and exit -v, --version print the version information and exit --boot-directory=DIR expect GRUB images under the directory DIR/grub instead of the /boot/grub directory ENTRY is a number or a menu item title. REPORTING BUGS
Report bugs to <bug-grub@gnu.org>. SEE ALSO
grub-reboot(8), grub-editenv(1) The full documentation for grub-set-default is maintained as a Texinfo manual. If the info and grub-set-default programs are properly installed at your site, the command info grub-set-default should give you access to the complete manual. grub-set-default (GRUB) 1.99-12ubuntu5 October 2011 GRUB-SET-DEFAULT(8)
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GRUB-EDITENV(1) User Commands GRUB-EDITENV(1) NAME
grub-editenv - edit GRUB environment block SYNOPSIS
grub-editenv [OPTION...] FILENAME COMMAND DESCRIPTION
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'. REPORTING BUGS
Report bugs to <bug-grub@gnu.org>. SEE ALSO
grub-reboot(8), grub-set-default(8) The full documentation for grub-editenv is maintained as a Texinfo manual. If the info and grub-editenv programs are properly installed at your site, the command info grub-editenv should give you access to the complete manual. grub-editenv (GRUB) 2.02-2ubuntu8.3 July 2018 GRUB-EDITENV(1)