[m-rev.] for review: improve dir./

[Zoltan Somogyi]

On 2023-09-13 12:26 +10:00 AEST, "Julien Fischer" <jfischer at opturion.com> wrote:
> The issue I encountered with MSVC is due to testing that FileName is
> the beginning of a current drive relative path here instead of DirName

Thanks for that. Looking back at the DIFF.dir I posted three days ago,
the bug was introduced there; until then, the test *was* on DirName.

Have you finished your review, so I can act on Peter's suggestions?

Zoltan.