5. Why call _create_locale if _WIN32_WINNT >= 0x0600 is true and loct is not used?
_create_locale can take bigger input than GetLocaleInfoEx. But we are interested in
language[_country-region[.code-page]]. We are using _create_locale to validate
the given input. The reason is we can't verify the locale name if it is appended with
code-page by using GetLocaleInfoEx. So before parsing, we verify if the whole input
locale name is valid by using _create_locale.I hope that answers your question.
Understood. In this case, _create_locale, is being used only to validate the input. Perhaps, in addition, you could create an additional function, which only validates winlocname, without having to create structures or use malloc, to be used when _WIN32_WINNT> = 0x0600 is true, but it is only a suggestion, if you think it is necessary.
Looking at the comments for IsoLocaleName() I see: "MinGW headers declare _create_locale(), but msvcrt.dll lacks that symbol". This is outdated [1][2], and _create_locale() could be used from Windows 8, but I think we should use GetLocaleInfoEx() as a complete alternative to _create_locale().