local socket = require"socket"

local group = "225.0.0.37"

local port = 12345

local c = assert(socket.udp())

--print(assert(c:setoption("reuseport", true)))

--print(assert(c:setsockname("*", port)))

--print(assert(c:setoption("ip-multicast-loop", false)))

--print(assert(c:setoption("ip-multicast-ttl", 4)))

--print(assert(c:setoption("ip-multicast-if", "10.0.1.3")))

--print(assert(c:setoption("ip-add-membership", {multiaddr = group, interface = "*"})))

local i = 0

while 1 do

    local message = string.format("hello all %d!", i)

    assert(c:sendto(message, group, port))

    print("sent " .. message)

    socket.sleep(1)

    c:settimeout(0.5)

    print(c:receivefrom())

    i = i + 1

end