std::latch::try_wait - cppreference.com

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std::latch

成员函数
latch::latch
latch::~latch
latch::count_down
latch::try_wait
latch::wait
latch::arrive_and_wait
常量
latch::max

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bool try_wait() const noexcept;		(C++20 起)

仅若内部计数器抵达零才返回 true。即使内部计数器抵达零，此函数亦可能以非常低的概率虚假地返回 false。

参数

（无）

返回值

以非常低的概率为 false，否则为 cnt == 0，其中 cnt 是内部计数器的值。

注解

容许虚假结果的原因是为允许实现使用比 std::memory_order_seq_cst 宽松的内存顺序。