I have:
unsigned char *foo();
std::string str;
str.append(static_cast(foo()));
The error: invalid static_cast from
unsigned char* is basically a byte array and should be used to represent raw data rather than a string generally. A unicode string would be represented as wchar_t*
According to the C++ standard a reinterpret_cast between unsigned char* and char* is safe as they are the same size and have the same construction and constraints. I try to avoid reintrepret_cast even more so than const_cast in general.
If static cast fails with what you are doing you may want to reconsider your design because frankly if you are using C++ you may want to take advantage of what the "plus plus" part offers and use string classes and STL (aka std::basic_string might work better for you)