isc_buffer_getuint8
addrlen = isc_buffer_getuint8(ecsbuf);
scopelen = isc_buffer_getuint8(ecsbuf);
addr[i] = isc_buffer_getuint8(ecsbuf);
isc_buffer_getuint8(&optbuf);
type = isc_buffer_getuint8(&optbuf);
isc_buffer_getuint8(isc_buffer_t *b);
c = isc_buffer_getuint8(source->pushback);