std::shared_mutex::shared_mutex
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                    < cpp | thread | shared mutex
                    
                                                            
                    
|   shared_mutex();  | 
(1) | (since C++17) | 
|   shared_mutex( const shared_mutex& ) = delete;  | 
(2) | (since C++17) | 
1) Constructs the mutex. The mutex is in unlocked state after the call.
2) Copy constructor is deleted.
Parameters
(none)
Exceptions
std::system_error if the construction is unsuccessful.
See also
|   C documentation for mtx_init 
 |