std::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 passed to std::call_once to group invocations of that function so that only one invocation results in execution of one of the functions passed to std::call_once.

Noncopyable.

[edit] Member functions

(constructor)	constructs the object (public member function)

[edit] See also

call_once (C++11)	invokes a function only once even if called from multiple threads (function template)