std::latch::count_down

 

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std::latch

Member functions

latch::latch

latch::~latch

latch::count_down

latch::try_wait

latch::wait

latch::arrive_and_wait

Constants

latch::max

 

void count_down(std::ptrdiff_t n =1);		(since C++20)

Atomically decrements the internal counter by n without blocking the caller.

If n is greater than the value of the internal counter or is negative, the behavior is undefined.

This operation strongly happens-before all calls that are unblocked on this latch.

Parameters

n

-

the value by which the internal counter is decreased

Return value

(none)

Exceptions

Throws std::system_error with an error code allowed for mutex types on error.