Yan Haibo <haibo(dot)yan(at)hotmail(dot)com> writes:
> Regarding the use of wcsncpy with LOCALE_NAME_MAX_LENGTH - 1, it is a precaution in case the input string is not null-terminated.
I don't think it's a "precaution". I think it's introducing a real
bug (that is, failure on a locale name of exactly the max allowed
length) to prevent a hypothetical bug.
regards, tom lane