WAV output(channels,samplerate);
output.NewFile("output.wav");

while(IsProcessing){
   ...
   output.Append(short_type_buffer,shift_size*channels);
}

output.Finish()

WAV input;
input.OpenFile("input.wav");

while(!input.IsEOF()){
   input.ReadUnit(short_type_buffer,shift_size*channels);
   ...
}

input.Finish();