protected:
virtual pos_type seekpos(pos_type sp,
std::ios_base::openmode which = std::ios_base::in | std::ios_base::out );
Repositions std::basic_streambuf::gptr and/or std::basic_streambuf::pptr, if possible, to the position indicated by sp.
Effectively executes seekoff(off_type(sp), std::ios_base::beg, which).
Parameters
sp - stream position, such as one obtained by seekoff() or seekpos() which - defines whether the input sequences, the output se