What does '&' mean in C++?

Question

What does \'&\' mean in C++?

As within the function

void Read_wav::read_wav(const string &filename)
{

}

And what is its equiv

Answer 1

In this particular case, std::string has a c_str method which returns a const char *. You can make a parallel C version and then have your C++ do something like:

void Read_wav::read_wav(const string &filename)
{
    do_read_wav(internal_read_wav, filename.c_str());
}

where do_read_wav is your C routine and internal_read_wav is a pointer to a C-style struct.

void do_read_wav(struct Read_wav rw, const char * filename)

Now, if you are storing information in the class, you need to make a C struct [all of the fields must be POD, etc]