Namespaces
Variants
Views
Actions

std::once_flag

From cppreference.com
< cpp‎ | thread
Revision as of 08:32, 19 November 2012 by 50.196.215.209 (Talk)

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 noncopyable.

Contents

Member functions

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
  

See also

Template:cpp/thread/dcl list call once