std::once_flag

 

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Definido no cabeçalho <mutex>
class once_flag;		(desde C++11)

The class std::once_flag is a helper structure for std::call_once.

An object of type std::once_flag that is passed to multiple calls to std::call_once allows those calls to coordinate with eachother such that only one of the calls will actually run to completion.

std::once_flag is noncopyable.

Funções de membro

std::once_flag::once_flag

once_flag();

Constructs an once_flag object. The internal state is set to indicate that no function has been called yet.

Parameters

(none)

Exceptions

noexcept specification:  

noexcept

  (desde C++11)

Veja também

call_once (C++11)	chama uma função apenas uma vez, mesmo se chamado de vários segmentos Original: invokes a function only once even if called from multiple threads The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (modelo de função)