I agree that no internal module function is safe, but MSVCRT is used by literally millions of developers, some of which have very uncommon functional requiremen

I agree that no internal module function is safe, but MSVCRT is used by literally millions of developers, some of which have very uncommon functional requirements, such as making their product work on a rare version of Windows. My empirical observation is that most developers are prone to the other extreme of not considering internals when they should.