Will this

const char* C4TimeMilliseconds::AsString() const
{
  StdStrBuf string;
  string.Format("%u:%02u:%02u:%03u:",time / 1000 / 60 / 60, (time / 1000 / 60) % 60, (time / 1000) % 60, time % 1000);
  return string.getData();
}

result in an invalid memory error?

As far as I understand StdStrBuf, it creates a pointer for the char data and cleans it up in the destructor. So, the destructor is already called after return, thus the method returns a pointer to invalid memory? If I am right, how to solve this?