std::basic_syncbuf<CharT,Traits,Allocator>::sync
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                    < cpp | io | basic syncbuf
                    
                                                            
                    |   protected: int sync() override;  | 
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First, records that a flush is pending, by updating the appropriate private flag.
Then, if the current emit-on-sync policy is true, makes a call to emit().
Otherwise (if the emit-on-sync policy is false, which is the default), the flush is suspended until emit() is called, such as through std::basic_osyncstream::emit() or std::basic_osyncstream::~basic_osyncstream
Parameters
(none)
Notes
sync() or its equivalent is implicitly called by close(), seekoff(), and seekpos() and explicitly called by std::basic_streambuf::pubsync()
Example
| This section is incomplete Reason: no example  | 
See also
|    [virtual]  | 
  synchronizes the buffers with the associated character sequence  (virtual protected member function of std::basic_streambuf<CharT,Traits>)  | 
  calls emit() on the underlying basic_syncbuf to transmit its internal data to the final destination (public member function of std::basic_osyncstream<CharT,Traits,Allocator>)  |