std::ungetwc
From cppreference.com
                    
                                        
                    
                    
                                                            
                    | Defined in header  <cwchar> | ||
| wint_t ungetwc( wint_t ch, std::FILE* stream ); | ||
Puts the wide character ch back to the given file stream. 
Only one wide character pushback is guaranteed.
[edit] Parameters
| ch | - | wide character to be put back | 
| stream | - | file stream to put the wide character back to | 
[edit] Return value
On success ch is returned.
On failure WEOF is returned and the given stream remains unchanged.
[edit] See also
| puts a character back into a file stream (function) | |
| gets a wide character from a file stream (function) | |
| C documentation for ungetwc | |


