On Windows, for historical reasons, file names such as aux.c, nul.txt are
not allowed. For aux.c, attempts to write such a file will result in an
obscure error, for nul.txt the call will succeed but no such file will
appear, ever, instead the effect will be equivalent to writing to /dev/null
on Linux/Unix.

Let's help users by refusing to create such files altogether, with an
informative error message.

Johannes Schindelin (2):
  mingw: short-circuit the conversion of `/dev/null` to UTF-16
  mingw: refuse paths containing reserved names

 compat/mingw.c        | 122 +++++++++++++++++++++++++++++++++++-------
 compat/mingw.h        |  11 +++-
 t/t0060-path-utils.sh |  13 ++++-
 3 files changed, 122 insertions(+), 24 deletions(-)

base-commit: 53a06cf39b756eddfe4a2a34da93e3d04eb7b728

Submitted-As: https://lore.kernel.org/git/pull.496.git.1576965901.gitgitgadget@gmail.com