On Windows, this macro defines an expression which evaluates to
TRUE if the code is running on a version of Windows where the wide
character versions of the Win32 API functions, and the wide character
versions of the C library functions work. (They are always present in
the DLLs, but don’t work on Windows 9x and Me.)
On non-Windows platforms, it is not defined.
|This function is not directly available to language bindings|