19 Diagnostics library [diagnostics]

19.5 System error support [syserr]

19.5.2 Class error_code [syserr.errcode]

19.5.2.5 Class error_code non-member functions [syserr.errcode.nonmembers]

error_code make_error_code(errc e) noexcept;

Returns: error_code(static_cast<int>(e), generic_category()).

bool operator<(const error_code& lhs, const error_code& rhs) noexcept;

Returns: lhs.category() < rhs.category() || lhs.category() == rhs.category() && lhs.value() < rhs.value().

template <class charT, class traits> basic_ostream<charT,traits>& operator<<(basic_ostream<charT,traits>& os, const error_code& ec);

Effects: os << ec.category().name() << ':' << ec.value().