Defined in header <thread>
template< class Clock, class Duration >
void sleep_until( const std::chrono::time_point<Clock,Duration>& sleep_time );
(since C++11)

Blocks the execution of the current thread until specified sleep_time has been reached.

Clock must meet the Clock requirements. The programs is ill-formed if std::chrono::is_clock_v<Clock> is false (since C++20).

The standard recommends that the clock tied to sleep_time be used, in which case adjustments of the clock may be taken into account. Thus, the duration of the block might, but might not, be less or more than sleep_time - Clock::now() at the time of the call, depending on the direction of the adjustment and whether it is honored by the implementation. The function also may block for longer than until after sleep_time has been reached due to scheduling or resource contention delays.


sleep_time - time to block until

Return value



Any exception thrown by Clock or Duration (clocks and durations provided by the standard library never throw).


#include <iostream>
#include <chrono>
#include <thread>
auto now() { return std::chrono::steady_clock::now(); }
auto awake_time() {
    using std::chrono::operator""ms;
    return now() + 2000ms;
int main()
    std::cout << "Hello, waiter...\n" << std::flush;
    const auto start {now()};
    std::chrono::duration<double, std::milli> elapsed {now() - start};
    std::cout << "Waited " << elapsed.count() << " ms\n";


Hello, waiter...
Waited 2000.17 ms

See also

stops the execution of the current thread for a specified time duration
C documentation for thrd_sleep

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