std::basic_filebuf::sync
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                    < cpp | io | basic filebuf
                    
                                                            
                    |   protected: 
virtual int sync()  | 
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If a put area exists (e.g. the file was opened for writing), calls overflow() to write all pending output to the file, then flushes the file as if by calling std::fflush.
If a get area exists (e.g. the file was opened for reading), the effect is implementation-defined. Typical implementation may empty out the get area and move the current file position back by the corresponding number of bytes.
Contents | 
[edit] Parameters
(none)
[edit] Return value
0 in case of success, -1 in case of failure.
[edit] Notes
sync() or its equivalent is implicitly called by close(), seekoff(), and seekpos() and explicitly called by std::basic_streambuf::pubsync()
[edit] Example
| This section is incomplete Reason: no example  | 
[edit] See also
|    invokes sync()  (public member function of std::basic_streambuf) 
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|    synchronizes an output stream with the actual file  (function)  |