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std::counting_semaphore::try_acquire_until(3) C++ Standard Libary std::counting_semaphore::try_acquire_until(3)

NAME

std::counting_semaphore::try_acquire_until - std::counting_semaphore::try_acquire_until

Synopsis


template<class Clock, class Duration>
bool try_acquire_until( const std::chrono::time_point<Clock, (since C++20)
Duration>& abs_time );


Tries to atomically decrement the internal counter by 1 if it is greater than
0; otherwise blocks until it is greater than 0 and can successfully
decrement the internal counter, or the abs_time time point has been passed.


The programs is ill-formed if std::chrono::is_clock_v<Clock> is false.

Preconditions


Clock meets the Clock requirements.

Parameters


abs_time - the earliest time the function must wait until in order to fail

Return value


true if it decremented the internal counter, otherwise false

Exceptions


May throw std::system_error or a timeout-related exception.

Notes


In practice the function may take longer than abs_time to fail.


Implementations are allowed to fail to decrement the counter even if it was greater
than 0 - i.e., they are allowed to spuriously fail and return false.

2022.07.31 http://cppreference.com