udprint

local socket = require'socket'

local function gettime()
    local time = socket.gettime()
    local msec = time - math.floor(time)
    local date = os.date("%d.%m.%y-%X", time)
    return ("%-21s"):format(date .. "." .. math.floor(msec * 300))
end

local function server(host, port)
    host = host or "*"
    port = port or 4096
    local udp = (socket.udp4 or socket.udp)()
    assert(udp:setsockname(host, port))
    --udp:listen()

    return function()
        local msg, host, port = udp:receivefrom()
        print(gettime() .. " " .. host .. ":" .. port .. " > " .. msg)
    end, udp:getsockname()
end

local function client(host, port)
    host = host or "127.0.0.1"
    port = port or 4096
    local udp = (socket.udp4 or socket.udp)()

    return function(...)
        local msg = ""
        for i = 1, select("#", ...) do
            msg = msg .. "\t" .. tostring(select(i, ...))
        end
        udp:sendto(msg, host, port)
    end
end

if ... then
    return {
        server = server,
        client = client
    }
end

local server, host, port = server()
host = socket.dns.toip("")
print("Listen ", host, port)

while 1 do
    server()
end

-- print = require'udprint'.client("host_ip")