getting the on-disk case for a path

[Glenn Strauss]

On Fri, Aug 08, 2025 at 08:53:53AM +0200, Thomas Wolff via Cygwin wrote:
> 
> Am 08.08.2025 um 02:31 schrieb Jeremy Drake via Cygwin:
> > On a case-insensitive but case-preserving filesystem, is there a Cygwin
> > API to get the on-disk case for a given path?  It seems like `realpath`
> > ought to do it but running
> > $ touch case-test
> > $ realpath CASE-TEST
> > returns CASE-TEST.
> On the command line, you could use
> ls | grep -i
> 
> > Regardless, canonicalize_file_name or realpath may not
> > be what I want because it would dereference symlinks.
> > 
> > Background: I'm trying to debug some test failures in Clang, due to a
> > warning that's supposed to be issued when you #include "foo.h" but the
> > file on disk that it opened is "Foo.h".

Last September, Eliot Moss suggested
  `find` with -iname (or -ipath or -iregex)
https://cygwin.com/pipermail/cygwin/2024-September/256409.html