> The alias is just adding confusion. If I see such an alias in code, I would wonder where else that function is used in the function, and be confused that it isn't
You'd be confused once or twice, then you'd learn the technique and you'd stop being confused. Every code pattern was unfamiliar to you at first. And confusing, until you internalized it. It's unrealistic to assume that you can ever stop learning new patterns - try switching to another language and you immediately have dozens of unfamiliar, confusing patterns to learn. (it gets better after a certain amount of languages known (like https://klibert.pl/articles/programming_langs.html) because you start noticing meta-patterns)
My C is rather rusty nowadays and using function pointer here may not be the best option, but as someone else said, there are other language tools for doing this kind of aliasing, like #define. I'd go for function pointer probably, because it reveals not only a name, but also a type of function and it's guaranteed not to escape the current scope (unless explicitly returned) while #define has no knowledge of scopes at all. In languages which support real macros, and preferably lexically scoped macros (like Racket) I'd use those. In languages with closures and first-class functions I'd probably do it in yet another way. But in general, if I find myself working with a name so long that it makes it hard to spot other names on the same line I will alias it locally.
You'd be confused once or twice, then you'd learn the technique and you'd stop being confused. Every code pattern was unfamiliar to you at first. And confusing, until you internalized it. It's unrealistic to assume that you can ever stop learning new patterns - try switching to another language and you immediately have dozens of unfamiliar, confusing patterns to learn. (it gets better after a certain amount of languages known (like https://klibert.pl/articles/programming_langs.html) because you start noticing meta-patterns)
My C is rather rusty nowadays and using function pointer here may not be the best option, but as someone else said, there are other language tools for doing this kind of aliasing, like #define. I'd go for function pointer probably, because it reveals not only a name, but also a type of function and it's guaranteed not to escape the current scope (unless explicitly returned) while #define has no knowledge of scopes at all. In languages which support real macros, and preferably lexically scoped macros (like Racket) I'd use those. In languages with closures and first-class functions I'd probably do it in yet another way. But in general, if I find myself working with a name so long that it makes it hard to spot other names on the same line I will alias it locally.
Have you read http://shop.oreilly.com/product/9780596802301.do ? It's a good, short book on the topic and it discusses exactly this issue at length in one of the chapters.