static int gen_check_bw(URLContext *s, RTMPContext *rt) { RTMPPacket pkt; uint8_t *p; int ret; if ((ret = ff_rtmp_packet_create(&pkt, RTMP_SYSTEM_CHANNEL, RTMP_PT_INVOKE, 0, 21)) < 0) return ret; p = pkt.data; ff_amf_write_string(&p, "_checkbw"); ff_amf_write_number(&p, ++rt->nb_invokes); ff_amf_write_null(&p); ret = ff_rtmp_packet_write(rt->stream, &pkt, rt->chunk_size, rt->prev_pkt[1]); ff_rtmp_packet_destroy(&pkt); return ret; }