CmdID / Commands
Convert a system path to a path relative to its filesystem root for GRUB. tldr-pages
On Linux
Opens CmdID with your command. It is read in your browser and sent nowhere.
Print the GRUB path of a file
grub-mkrelpath path/to/file
Print the GRUB path of a file on a separately mounted filesystem
grub-mkrelpath /mnt/partition/path/to/file