[ESS] Following up, success! [was RE: [R-win] Difficulty installing R packages under Windows 11 / Cygwin]

[Martin Maechler]

>>>>> Robert Lerche via ESS-help 
>>>>>     on Wed, 3 Jan 2024 22:58:00 +0000 writes:

    > Yes and thanks for responding.  That is I think exactly what's needed and I have taken a shot at implementing it.  [I'm glad my previous attached patch got filtered, I was a bit careless.]  Here's a summary of what I've done:
    > ess-custom.el: extract prefix using cygpath, set to nil if error (i.e., no cygpath command indicates not in Cygwin)

Just to be sure: So all these changes in your patch are
guaranteed to *not* change the path / file-paths  anywhere
*unless* our emacs & ESS run on an Windows Cygwin  platform?

Martin