std::codecvt::unshift, do_unshift
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                    | Defined in header  <locale> | ||
| public: result unshift( StateT& state, | (1) | |
| protected: virtual result do_unshift( StateT& state, | (2) | |
1) public member function, calls the member function 
do_unshift of the most derived class.2) if the encoding represented by this 
codecvt facet is state-dependent, and state represents a conversion state that is not the initial shift state, writes the characters necessary to return to the initial shift state. The characters are written to a character array whose first element is pointed to by to. No more than to_end-to characters are written. The parameter to_next is updated to point one past the last character written.Return value
A value of type std::codecvt_base::result, indicating the success status as follows:
| ok | all necessary characters were written. statenow represents initial shift state | 
| partial | not enough space in the output buffer. to_next == to_end | 
| error | unspecified error occurred | 
| noconv | the encoding is not state-dependent, no termination sequence necessary | 
The non-converting specialization std::codecvt<char, char, std::mbstate_t> always returns std::codecvt_base::noconv
Notes
This function is called by std::basic_filebuf::close() and in other situations when finalizing a state-dependent multibyte character sequence.
Example
| This section is incomplete Reason: no example | 
See also
| converts a wide character to its multibyte representation, given state (function) | |
| [virtual] | converts a string from internT to externT, such as when writing to file (virtual protected member function) |