cmol

addr_info = Addrinfo.new(client)
puts "Client connected from #{addr_info.ip_address} using " +
  "#{addr_info.ipv6_v4mapped? ? "IPv4" : "IPv6"}"

cmol

irb(main):003:0> Socket.getaddrinfo("localhost", 12345, :AF_UNSPEC, :DGRAM)
=> [
     ["AF_INET6", 12345,       "::1",       "::1", 10, 2, 17],
     ["AF_INET",  12345, "127.0.0.1", "127.0.0.1",  2, 2, 17]
   ]

cmol

Socket.getaddrinfo(CONNECT_ADDR,CONNECT_PORT, :AF_UNSPEC, :DGRAM).each do | con |
  af, port, hostname, ip, pf, sock_type, ipproto = con
  Addrinfo.udp(ip, port).connect do |socket|
    socket.send("Connected via #{af}", FLAGS)
    message, server = socket.recvfrom(MSG_LENGTH)
    puts message
  end
end

cmol

cmol@qui-gon:~$ ruby echo_client_udp.rb
[IPv6] Connected via unspecified address family socket
[IPv6] Connected via AF_INET6
[IPv4] Connected via AF_INET

cmol

require "socket"

CONNECT_ADDR = "localhost"
CONNECT_PORT = 12345
MSG_LENGTH  = 256
FLAGS       = 0

Addrinfo.udp(CONNECT_ADDR, CONNECT_PORT).connect do |socket|
  socket.send("Connected via unspecified address family socket", FLAGS)
  message, server = socket.recvfrom(MSG_LENGTH)

cmol

def get_interface_info(name)
  ifaddrs = Socket.getifaddrs.reject do |ifaddr|
    !ifaddr.addr&.ipv6_linklocal? || (ifaddr.flags & Socket::IFF_MULTICAST == 0)
  end
  ifaddrs.select! {|ifaddr| ifaddr.name == name } if name
  ifaddrs.map {|ifaddr| [ifaddr.name, ifaddr.ifindex, ifaddr.addr.ip_address] }
end

cmol

def echo_listener(socket, linklocal_addr, multicast_addr, multicast_port,
                  flags, msg_length)
  loop do
    # Listen for messages of up to specified length
    message, client = socket.recvfrom(msg_length)

    # Extract client information given as array and log connection
    addr_info = Addrinfo.new(client)

    # We are not interested in messages from our selves

cmol

[["if_name", index, "ip_address"],[...]]

cmol

require 'socket'
require 'ipaddr'

def get_interface_info(name)
  ifaddrs = Socket.getifaddrs.reject do |ifaddr|
    !ifaddr.addr&.ipv6_linklocal? || (ifaddr.flags & Socket::IFF_MULTICAST == 0)
  end
  ifaddrs.select! {|ifaddr| ifaddr.name == name } if name
  ifaddrs.map {|ifaddr| [ifaddr.name, ifaddr.ifindex, ifaddr.addr.ip_address] }
end

cmol

cmol@third-host:~$ ruby src/multicast.rb
Using local interface enp0s3 with address fe80::a00:27ff:fe07:dea6%enp0s3
========= Sending echo REQUEST from fe80::a00:27ff:fe07:dea6%enp0s3
[REPLY]   Hello from fe80::71c0:aa40:6d16:7c59%wlp4s0
[REPLY]   Hello from fe80::ade4:80af:c170:6340%enp0s31f6