How to get the username in C/C++ in Linux?

Question

How can I get the actual \"username\" without using the environment (getenv, ...) in a program?

Answer 1

working a little bit through modern c++ specs

static auto whoAmI = [](){ struct passwd *tmp = getpwuid (geteuid ());
  return tmp ? tmp->pw_name : "onlyGodKnows"; 
}