std::once_flag
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once_flag
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Defined in header
<mutex>
class once_flag;
(since 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 each other such that only one of the calls will actually run to completion.
std::once_flag is neither copyable nor movable.
[edit] Member functions
std::once_flag::once_flag
constexpr once_flag() noexcept;
Constructs an once_flag object. The internal state is set to indicate that no function has been called yet.
Parameters
(none)
[edit] See also
(C++11)
(function template) [edit]
C documentation for once_flag