static int get_packetheader(NUTContext *nut, ByteIOContext *bc)
static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int prefix_length)
static int get_packetheader(NUTContext *nut, ByteIOContext *bc){    nut->curr_frame_start = url_ftell(bc);    nut->curr_frame_size = get_v(bc);    nut->last_frame_size = get_v(bc);    dprintf("Packet: fwd: %d bwd: %d\n",	nut->curr_frame_size, nut->last_frame_size);        return 0;}