The semantics used in parsing the configuration file are the following:

• The files must be in plain-text format.

• ‘#’ at the beginning of a line in a configuration file means it is only a comment.

• Options are separated by spaces.

• All numbers can be either decimal or hexadecimal. A hexadecimal number must be preceded by ‘0x’, and is case-insensitive.

These commands can only be used in the menu.

menuentry

Command: menuentry title [--class=class …] [--users=users] [--unrestricted] [--hotkey=key] [--id=id] [arg …] { command; … }

This defines a GRUB menu entry named title. When this entry is selected from the menu, GRUB will set the chosen environment variable to value of --id if --id is given, execute the list of commands given within braces, and if the last command in the list returned successfully and a kernel was loaded it will execute the boot command.

The --class option may be used any number of times to group menu entries into classes. Menu themes may display different classes using different styles.

The --users option grants specific users access to specific menu entries. See Security.

The --unrestricted option grants all users access to specific menu entries. See Security.

The --hotkey option associates a hotkey with a menu entry. key may be a single letter, or one of the aliases ‘backspace’, ‘tab’, or ‘delete’.

The --id may be used to associate unique identifier with a menu entry. id is string of ASCII aphanumeric characters, underscore and hyphen and should not start with a digit.

All other arguments including title are passed as positional parameters when list of commands is executed with title always assigned to $1.

submenu

Command: submenu title [--class=class …] [--users=users] [--unrestricted] [--hotkey=key] [--id=id] { menu entries … }

This defines a submenu. An entry called title will be added to the menu; when that entry is selected, a new menu will be displayed showing all the entries within this submenu.

All options are the same as in the menuentry command (see menuentry).