std::char_traits::eof
From cppreference.com
                    
                                        
                    < cpp | string | char traits
                    
                                                            
                    |   static int_type eof(); 
 | 
(until C++11) | |
|   static constexpr int_type eof(); 
 | 
(since C++11) | |
Returns a value not equivalent to any value of type char_type.
Contents | 
[edit] Parameters
(none)
[edit] Return value
A value not equivalent to any value of type char_type.
[edit] Exceptions
| (none) | (until C++11) | 
|   
noexcept specification:   
noexcept    | 
(since C++11) | 
[edit] Complexity
Constant.
[edit] See also
|    [static] 
 | 
   checks whether a character is eof value  (public static member function)  |