std::atomic_flag::clear
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                    < cpp | atomic | atomic flag
                    
                                                            
                    |   Defined in header  <atomic>
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|   void clear( std::memory_order order = std::memory_order_seq_cst ) volatile noexcept;  | 
(1) | (since C++11) | 
|   void clear( std::memory_order order = std::memory_order_seq_cst ) noexcept;  | 
(2) | (since C++11) | 
Atomically changes the state of a std::atomic_flag to clear (false).
Parameters
| order | - | the memory synchronization ordering for this operation (cannot be std::memory_order_consume, std::memory_order_acquire, or std::memory_order_acq_rel) | 
See also
|    atomically sets the flag to true and obtains its previous value   (public member function)  | |
|    (C++11)(C++11)  | 
   atomically sets the value of the flag to false   (function)  | 
|    (C++11)  | 
   defines memory ordering constraints for the given atomic operation   (enum)  |