I still think I might eventually get around to writing a separate Win32::ErrorMode module for clarity

Certainly wouldn't hurt. It's not entirely expected that error modes would be handled by a module named Win32API::File. I actually remembered from a long time ago that the function was covered by a perl module ... couldn't remember the name of the module, so found it by searching an old perl 5.6 installation for all files that contained "SetErrorMode".

As an aside, I have a long-abandoned module sitting on one of my much-disused Windows boxes called Win32::YAWN - Yet Another Windows Module (with mandatory and appropriate typo). It contains, among other ad-hoc Win32 API wrappings, an XSub that wraps SetErrorMode.

You had better be quick ;-)

Cheers,
Rob