What is the point of this function? In rust, there's no equivalent to sprintf?

In fairness, C standard library functions mostly look like magic incantations to me (I think due in large part to the old-school convention of abbreviating function names). malloc, sprintf, atoi, etc don't exactly read like english... (unless you happen to already know what they stand for)

Also, aho-corasick comes from the name of this algorithm that is named after its inventors https://en.wikipedia.org/wiki/Aho%E2%80%93Corasick_algorithm

atoi is a classic example of the sort of bad naming C has long been infamous for. It's not a word, it's an initialism, and the common documentation for it doesn't even say what the initialism actually means. It's relatively easy to infer what it means from the description of what it does (ascii to integer), but can easily be incorrectly inferred ([character] array to integer.)

C kind of gets a pass for this stuff because C was old and in the early days they were limited by token size. But to still be using this term today in a new language seems fairly derisible.