Well, they simply couldn't, as in '86, ANSI C did not "exist" (officially) yet as the first ANSI C standard was ratified in 1989 (C89), with slight updates in 1990 (C90). And it would have taken a lot of magic to forsee C99...
Ralf
Of course they couldn't. That's exactly why...
I only wish books of such quality have been around when I was taught the original K&R C programming language
(my comment was about the quality of King's book, not about covering C99).