atomic_flag
From cppreference.com
                    
                                        
                    
                    
                                                            
                    | Defined in header  <stdatomic.h> | ||
| typedef /* unspecified */ atomic_flag; | (since C11) | |
atomic_flag is an atomic boolean type. Unlike other atomic types, it is guaranteed to be lock-free. Unlike atomic_bool, atomic_flag does not provide load or store operations.


