As far as I'm aware, the binary mode in C & C++ is only "useful" on Windows. (
The doc reads: "POSIX implementations do not distinguish between text and binary streams".) But this ain't your issue right now.
You have to be aware that SFML does
not intend to provide replacement for S(T)L features; on the contrary, when switching to C++11 (or any more recent standard), SFML will drop some of its features in favour of S(T)L implementations. So if one wants something to be added to SFML, one would have to build a strong use case scenario.
Now, yes, the
std::fstream::write operation (actually inherited from
std::basic_ostream) only takes C strings as arguments but that's not an issue at all. First of all, using
void* is really not recommended as a general practice in C++. Secondly, you have the
std::basic_ostream::operator<< family of operators at your disposal for printing more complex types, like you would do it with
std::cout, for example.