Query about GRUB comand line functionality

[Bret Busby]

Hello.

I have a system that shows as having "GRUB version 2.02-beta2"

The system is completely broken, due to attempting to install an extra
operating system, which now appears to me, to be a trojan horse.

The system previously had installed, MS Windows 8 (which got lost,
when Debian Linux was installed, but, the loss of MS Windows 8, on
that computer, has not been a problem, for me), Debian Linux 7.x and
Ubuntu Linux 14.04 LTS.

That is the order in which the operating systems were installed,
before the additional one broke the system.

When Debian Linux was added, GRUB showed only the Debian Linux OS.

When Ubuntu Linux was added, the Ubuntu GRUB showed the boot options
of Ubuntu and Debian.

When the trojan horse operating system was added, the bootloader shows
only the trojan horse operating system, which does not boot.

In trying to restore the system to the state before the trojan horse
operating system, I have found how to get to a GRUB command line
prompt, which shows above specified version of GRUB as being present.

The computer is a GPT/UEFI system, and shows as having 13 GPT partitions.

I have found a web site that gives some commands, at
http://www.linux.com/learn/tutorials/776643-how-to-rescue-a-non-booting-grub-2-on-linux/

My query is this; given the specified version of GRUB, and, given that
the computer does not have an operable operating system, does the GRUB
command line that is present, have the functionality of being able to
mount (and then, later, to unmount) a USB thumb drive, and then create
a file on the thumb drive, and, from a start point to an end point,
write all commands entered, and the respective output responses, so as
to be able to save to the file, text that can be conveyed to a mailing
list, showing exactly what commands are entered, and the response for
each command entered, for seeking a solution to restore and repair the
system?

I have a memory, from some (about 3, I think) decades ago, of DEC
RSTS/e providing this kind of functionality (the writing of the
commands entered, and their responses, to a file, but, not the part
about the USB thumbdrives, which were not yet invented and available,
at that time), on PDP 11's (I had used it on a PDP 11/44).

Thank you in anticipation.

-- 
Bret Busby
Armadale
West Australia
..............

"So once you do know what the question actually is,
 you'll know what the answer means."
- Deep Thought,
 Chapter 28 of Book 1 of
 "The Hitchhiker's Guide to the Galaxy:
 A Trilogy In Four Parts",
 written by Douglas Adams,
 published by Pan Books, 1992

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