While the "feh" slideshow keys "spacebar" & "backspace" scroll through the photos in the folder, and "esc" will exit the program, the only thing left is the "move" or "copy" slideshow command.
I see from the "feh" manpages that the "f" or "F" slideshow key is not what we need:
But, the "save" slideshow key seems to (silently) do the trick:
f, F Save the current filelist to a unique filename.
So, here's the use model:
s, S Save the current image to a unique filename.
This is fast (much faster than any other editing program on Ubuntu to date), intuitive (works almost the same as Irfanview, the admitted leader in simple photo manipulation), and easy.
a) Given a directory of photos, e.g., /media/Flash Drive/pictures
b) Create a sub directory to hold files, e.g., mkdir "/media/Flash Drive/pictures/save"
c) Go to that sub directory, e.g., cd !$
d) Run "feh" in any desired mode, e.g., "feh .." or "feh -F .."
e) Use the "spacebar" to step forward through the picture set
f) Use the "backspace" key to step backward through the picture set
g) Use the "S" (or "s") key to silently copy the file to the current directory
h) Use the "Esc" key to escape out of the program
Thanks for the help! I hope others benefit if they find this in their google searches.