process_ancillary_data
ssize_t (*process_ancillary_data)(net_protocol* self,
status = process_ancillary_data(socket, container, header, flags);
status = process_ancillary_data(socket, buffer, header, flags);
if (socket->first_info->process_ancillary_data == NULL)
ssize_t bytesWritten = socket->first_info->process_ancillary_data(
status_t status = process_ancillary_data(socket, ancillaryData, header,