how does one securely clear std::string?

Question

How does one store sensitive data (ex: passwords) in std::string?

I have an application which prompts the user for a password and passes it to a downstr

Answer 1

std::string mystring;
...
std::fill(mystring.begin(), mystring.end(), 0);

or even better write your own function:

void clear(std::string &v)
{
  std::fill(v.begin(), v.end(), 0);
}