std::basic_streambuf::showmanyc
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                    < cpp | io | basic streambuf
                    
                                                            
                    |   protected: std::streamsize showmanyc();  | 
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Estimates the number of characters available for input in the associated character sequence. underflow() is guaranteed not to return traits::eof() until at least that many characters are extracted.
Contents | 
[edit] Parameters
(none)
[edit] Return value
The number of characters available in the sequence, or -1 if no characters are available. In that case, underflow() and uflow() will fail.
The base class version returns 0.
[edit] Example
| This section is incomplete Reason: no example  | 
[edit] See also
|    obtains the number of characters immediately available in the get area  (public member function)  | |
|    [virtual]  | 
   optionally provides the number of characters available for input from the file  (virtual protected member function of std::basic_filebuf)  |