Objects of class steady_clock represent clocks for which values of time_point never decrease as physical time advances and for which values of time_point advance at a steady rate relative to real time. That is, the clock may not be adjusted.
class steady_clock {
public:
using rep = unspecified;
using period = ratio<unspecified, unspecified>;
using duration = chrono::duration<rep, period>;
using time_point = chrono::time_point<unspecified, duration>;
static constexpr bool is_steady = true;
static time_point now() noexcept;
};