gistfile1.txt

#include <iostream>
#include <string>

struct base
{
        virtual ssize_t write(const char *buf, size_t buf_len);
        ssize_t write(std::string &s);
};

ssize_t base::write(const char *buf, size_t buf_len)
{
        std::cout << "base::write(char *)" << std::endl;
}

ssize_t base::write(std::string &s)
{
        std::cout << "base::write(string)" << std::endl;
        return write(s.data(), s.size());
}

struct derived : base
{
        using base::write;
        virtual ssize_t write(const char *buf, size_t buf_len);
};

ssize_t derived::write(const char *buf, size_t buf_len)
{
        std::cout << "derived::write(char *)" << std::endl;
}

int main()
{
        std::string s;
        base b;
        derived d;
        b.write("", 0);
        b.write(s);
        d.write("", 0);
        d.write(s);
}