Using a Debian Live image to Invoke a Rescue Shell

["Martin McCormick" <martin.m@suddenlink.net>]

I don't know if things have changed or I forgot how to do this
but I want to boot in to a Debian image and not install it but
invoke a shell so as to clone the hard drive on a Windows machine
to an external hard drive.

	For computer users who are blind, this is a real boon in
situations like this because most Linux systems these days can be
made to boot talking by striking S when the OS starts to boot.

	You hear, in English first, "Choose your language."

	It is, of course, the same setup screen everybody sees so
one needs to set language, keyboard and general location to get
started.

	If one wants, they can go through the setup and install
the whole works but, in this case, I am doing this because I had
a stupid moment and wiped out my Windows home directory
after a batch file (shell script) got away from me and zapped
every file in my home directory instead of one folder I was
trying to zero out.  Go ahead and laugh.

	The idea is to clone the internal drive and then try
recovering the deleted files.  If something further goes wrong,
I've still got all the pieces.

	I remember doing this same thing a few years ago and
there is some way to break out of the setup screen and invoke a
bash-like shell in order to run mount/umount and dd.  Since I
boot it talking, all these applications still talk.  After all,
it's unix and the speech synthesizer was patched in to standard
output right from boot.  I don't remember exactly what special
key sequence I hit to invoke the shell but need to refresh my
memory or learn the new procedure.

	After learning how to get a relatively new HP Pavilion to
boot from a usb device, I think that most all the UFI-bootable
images will boot.  The one I just tried which did boot is
debian-10.2.0-amd64-DVD-1.iso

	I've also got

debian-live-10.2.0-amd64-mate.iso and debian-10.3.0-amd64-netinst.iso

	The netinst image is only 350 MB while the dvd-1 image is
about 4 GB.  The mate image is around 2.5 GB.

	Thanks for any and all constructive suggestions as to how
to go from Setup to recovery shell.

Martin McCormick