My criticisms are only partially stylistic, but also that people copy this code to other situations and it breaks. So, I'm showing them why it only works in that one specific context and how to break the code.
If I can make a suggestion, then. I apologize if you've already covered this elsewhere in your book, but:
Please encourage the use of the "restrict" keyword to encourage proper aliasing optimization by compilers.
Also, would it be worth considering, perhaps in a chapter on how-to-deal-with-C-style-strings-if-you-must, including a section on writing compiler-independent macros to emulate safer calls like the str*_s variants in VS. These functions are usually slightly-different in incantation across VS and GCC, so it might be helpful to abstract them. It also is a relatively simple exercise in preprocessor macros with a clear benefit.
