once_flag Structure

The latest version of this topic can be found at once_flag Structure.

Represents a struct that is used with the template function call_once to ensure that initialization code is called only once, even in the presence of multiple threads of execution.

Syntax

struct once_flag { constexpr once_flag() noexcept; once_flag(const once_flag&); once_flag& operator=(const once_flag&); };

Remarks

The once_flag``struct has only a default constructor.

Objects of type once_flag can be created, but they cannot be copied.

Requirements

Header: mutex

Namespace: std

See Also

Header Files Reference
<mutex>