tl;dr

http://www.nedprod.com/programs/portable/nedtries/

https://github.com/ned14/nedtries/blob/master/test.c

While we usually take associative array/dictionary/hash data structure as granted in modern programming languages, there is no such thing builtin in a good old C. It might be tempting to use SQLite or even Berkeley DB to fullfil that urge in many project, but the extra dependency handling is a PITA.

Plus, there are many tasks that do not require ACID neither persistent storage.

Even a red-black tree could be an overkill sometimes. Then, there is a bitwise trie. One particular implementation, nedtries, caught my attention: