std::basic_syncbuf<CharT,Traits,Allocator>::basic_syncbuf
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                    < cpp | io | basic syncbuf
                    
                                                            
                    | basic_syncbuf() : basic_syncbuf(nullptr) | (1) | |
| explicit basic_syncbuf( streambuf_type* obuf ) : basic_syncbuf( obuf, Allocator() ) {} | (2) | |
| basic_syncbuf( streambuf_type* obuf, const Allocator& a); | (3) | |
| basic_syncbuf( basic_syncbuf&& rhs); | (4) | |
1) Default constructor: creates an instance of 
std::basic_syncbuf with emit-on-sync policy set to false, wrapped streambuffer set to nullptr, and using default-constructed Allocator as the allocator for temporary storage.  2,3) Creates an instance of 
std::basic_syncbuf with emit-on-sync policy set to false, wrapped streambuffer set to obuf, and using a as the allocator for temporary storage. 4) Move constructor: move-constructs a 
std::basic_syncbuf object by moving all contents from another std::basic_syncbuf object rhs, including the temporary storage, the wrapped stream pointer, policy, and all other state (such as the mutex pointer). After move, rhs is not associated with a stream, and rhs.get_wrapped()==nullptr. The put area member pointers of the base class std::basic_streambuf of rhs are guaranteed to be null. Destroying a moved-from rhs will not produce any output.Parameters
| obuf | - | pointer to the std::basic_streambuf to wrap | 
| a | - | the allocator to use for temporary storage | 
| rhs | - | another std::basic_syncbuf to move from | 
Exceptions
2,3) May throw std::bad_alloc from the constructor of the internal temporary storage or std::system_error from the mutex construction.
Notes
Typically called by the appropriate constructors of std::basic_osyncstream.
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>) | 
| atomically transmits the entire internal buffer to the wrapped streambuf (public member function) |