With UEFI firmware you get also an "UEFI Shell" or "EFI shell" that looks a bit like GRUB shell or old DOS shell. Both unix/linux and DOS commands can be used, for example ls or dir are similar (or identical).

Basics

When you boot in EFI shell (way to do so depends of the UEFI firmware) you get a

EFI>

prompt.

Disks are "fs0", "fs1", etc. It's a DOS way: partitions are seen as disks.

If you type EFI>ls <RC>

(<RC> meaning press "Enter"), you get an error message, there is nothing to list there. But try (notice the ":")

fs0:

you probably get

fs0:\EFI>

if the fs0 partition exists (it could be a nonexistent floppy). Try 1, 2...

Removing

For example, I had to remove old no more necessary entries in the EFI partition. This one was (for me) in fs0, so

fs0:\EFI>ls

listed

Microsoft opensuse boot 32

rm opensuse

allowed me to remove the opensuse folder. Beware, this "rm" do not need any option to remove a directory, it however ask for permission first.

Completion and keyboard help

TAB completion works ala Windows way: typing an initial and TAB key gives the first file beginning with this initial. Typing TAB again gives the next one.

EFI Shell is not case dependent. Typing "w" find also "W".

up and down arrows gives access to the key history

list

ls (or DIR) gives a list. option -a shows hidden files, there they are prefixed by "$", not ".".

ls -b stops the display at the windows limit, allowing one to see long display.

One can't aggregate options, -ab is not recognized, one have to type -a -b.

File content

type <filename>

List the content of the file.