I didn't see it yet from a quick skim of the available chapters, but I'm going to guess that his preferred alternative is 'bstr - The Better String Library' - http://bstring.sourceforge.net/
I've used it the past, and I try to include it in any project that isn't immediately trivial, although the to/from integration with just about all library code ever is a bit of a hassle.
It's not just that the to/from is a hassle, it's also that you have to deeply understand the gotchas of ASCIIZ strings to safely do that bridging at all --- so pretending it doesn't exist is probably not a good teaching strategy. (I have no opinion about the article and am only commenting on this thread because I like C).
I do not pretend anything about null-terminated strings in the book. In fact, I have many exercises and assignments where they use Valgrind to buffer overflow C strings repeatedly and don't introduce bstring until much later.
I've used it the past, and I try to include it in any project that isn't immediately trivial, although the to/from integration with just about all library code ever is a bit of a hassle.