std::counting_semaphore<LeastMaxValue>:: try_acquire

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std::counting_semaphore
bool try_acquire ( ) noexcept ;
(since C++20)

Tries to atomically decrement the internal counter by 1 if it is greater than ​ 0 ​ ; no blocking occurs regardless.

Return value

true if it decremented the internal counter, otherwise false .

Notes

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 .

See also

increments the internal counter and unblocks acquirers
(public member function)
decrements the internal counter or blocks until it can
(public member function)
tries to decrement the internal counter, blocking for up to a duration time
(public member function)
tries to decrement the internal counter, blocking until a point in time
(public member function)
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