filebuf::uflow

int uflow ( );

For the purpose of stream buffers, underflows happen when a new character is to be read at the get pointer gptr, but this has reached the end pointer egptr, indicating that no more characters are apparently available in the internal input array.

This function is expected to modify the eback, gptr and egptr pointers that define the internal input array in such a way that if there are more characters available in the controlled input sequence after the location represented by streambuf::egptr, at least some of them are made available through this internal input array. In this case, the function returns the new character pointed by the get pointer and advances it one position. Otherwise, if there are no more characters available in the controlled input sequence after the one represented by egptr, the function returns EOF (or traits::eof() for other traits).

This member function overrides the inherited virtual member streambuf::underflow.

The behavior of this member function is the same as the one of underflow except that this function also advances the get pointer by one position.

Parameters

none

Return Value

The new character available at the current get pointer position, if any. Otherwise, EOF (or traits::eof() for other traits) is returned.

Basic template member declaration

( basic_filebuf<charT,traits> )


See also.