demo · v144
Multicast Receiver
Configure a multicast group and watch the page attempt to open a UDPSocket. Outside an Isolated Web App the call fails — the page then runs a simulated mDNS listener so you can see what the read stream would surface.
Direct Sockets / UDPSocket multicast is restricted to Isolated Web Apps. Outside an IWA the API isn't exposed; the demo will fall through to a simulated mDNS responder so you can still see the shape.
UDPSocket present:
checking…
no activity
the API
const sock = new UDPSocket({
remoteAddress: "224.0.0.251",
remotePort: 5353,
multicast: { interfaces: ["wlan0"], ttl: 1 },
});
await sock.opened;
const reader = sock.readable.getReader();
while (true) {
const { value, done } = await reader.read();
if (done) break;
console.log(value.remoteAddress, value.data);
}