You can, but idiomatic Rust code looks pretty different from idiomatic C code - to give a concrete example,

    int get_a_string(char **out) // returns error code

could be translated literally as

    fn get_a_string(out: *mut *mut c_char) -> c_int

but much preferable would be

    fn get_a_string() -> Result<String, Errcode>

[where Result and String are standard library types; Errcode would be a custom enum.]

I suppose you could go from the first to the second incrementally, then refactor to the third. But I'm not sure it'd work well.