get_file_size
ret = get_file_size(in_fname, &raw_data_len);
ret = get_file_size(in_sig_fname, &to_read);
ret = get_file_size(scalar_file, &buf_len);
ret = get_file_size(point_file, &buf_len);
ret = get_file_size(in_fname, &raw_data_len);