m_i_streambuf = new wxStreamBuffer(wxStreamBuffer::read);
m_i_streambuf->SetBufferIO(len); // create buffer
stream.CopyTo(m_i_streambuf->GetBufferStart(), len);
m_i_streambuf = new wxStreamBuffer(wxStreamBuffer::read);
m_i_streambuf->SetBufferIO(len); // create buffer
stream.CopyTo(m_i_streambuf->GetBufferStart(), len);