strstreambuf::underflow
A protected virtual function to extract the current element from the input stream.
virtual int underflow( );
Return Value
If the function cannot succeed, it returns EOF. Otherwise, it returns the current element in the input stream, converted as described above.
Remarks
The protected virtual member function endeavors to extract the current element ch from the input buffer, then advance the current stream position, and return the element as (int)(unsigned char)ch. It can do so in only one way: if a read position is available, it takes ch as the element stored in the read position and advances the next pointer for the input buffer.
Requirements
Header: <strstream>
Namespace: std