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.
(none).
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".
The name of this function stands for "stream: how many characters?", so it is pronounced "S how many C", rather than "show many C"
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<CharT,Traits> ) |
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