char *inner_data = pending_data.data() + sizeof(metacube2_block_header);
if (flags & METACUBE_FLAGS_HEADER) {
stream_header = string(inner_data, inner_data + size);
char *inner_data = pending_data.data() + sizeof(metacube2_block_header);
if (flags & METACUBE_FLAGS_HEADER) {
stream_header = string(inner_data, inner_data + size);