I tracked down a bug where octave has a function called 'copyfile' which
shells out to call 'cp -r' but in an environment without coreutils, or
when in a script with PATH unset, it fails.

try it out with the following:
touch foo
guix environment --pure --ad-hoc octave-cli -- \
    octave --eval 'copyfile("foo","bar");'

-- 
Efraim Flashner   <efraim@flashner.co.il>   אפרים פלשנר
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