call.adv.sendWrtcCmd() is used to transmit data to other end of a call using RTCgate signaling channel.
It is intended to send small amounts of user commands and arguments to the remote client. For large amounts of data use data channel instead.
call.adv.sendWrtcCmd(data)
Nothing.
Will trigger wrtc.onWrtcCmd() at receiving end.
call.adv.sendWrtcCmd({cmd:"yourcmd", data:"yourdata"});