std::basic_streambuf::showmanyc
protected: virtual std::streamsize showmanyc(); |
||
Estimates the number of characters available for input in the associated character sequence. underflow() is guaranteed not to return Traits::eof() or throw an exception until at least that many characters are extracted.
Parameters
(none)
Return value
The number of characters that are certainly available in the associated character sequence, or -1 if showmanyc
can determine, without blocking, that no characters are available. If showmanyc
returns -1, underflow() and uflow() will definitely return Traits::eof or throw.
The base class version returns 0, which has the meaning of "unsure if there are characters available in the associated sequence".
Notes
The name of this function stands for "stream: how many characters?", so it is pronounced "S how many C", rather than "show many C"
Example
This section is incomplete Reason: no example |
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 ) |