>>32580 (OP)I haven't read it, but from what I know it covers K&R C rather than ANSI C89 (or ISO C90, which most compilers implement and call C89 or something). If you don't know or understand C very well, it may be worth the read.
Otherwise I'd recommend reading The Art of Computer Programming by Donald Knuth, specifically the first volume. It teaches you the fundamentals of trees and useful manipulations you can apply to them. It teaches these concepts in an ancient hypothetical punch-card programming language called MIX. You are provided nothing but the absolute bare-minimum. The assembly language still provides a great deal of meta-programming through homogeneity of instructions and data, but this concept isn't as useful as it once was. Still a very interesting and insightful read.
Newer volumes of the book should come with instructions in MIXAL instead of MIX, which is far closer to modern systems running AMD64/AARCH64.