If there’s one thing I don’t like about the whole class of formatting strings in C is that you loose all forms of type safety while using it. Yes a compiler like GCC (too my knowledge the only one atually) still performs type checking and gives you warnings (which I always turn into errors) when you have type mismatches… But still, I like an approach like Boost.Format’s much better (i.e. you don’t loose the type safety of the language).