UTF-8 Filenames on Windows

[Joseph Wright]

Hello all,

Testing some upcoming LaTeX kernel code, I find something unexpected on 
Windows. With a suitable file and minimal input

\openin1 foo€€€.eps %
\ifeof1 %
\T
\else
\F
\fi
\bye

I get "\T" for Windows TeX Live binaries (pdfTeX/XeTeX/LuaTeX) but "\F" 
on Linux or using a MiKTeX installation.

Other UTF-8 chars give a similar issue.

A bug or a feature?

Joseph