package main

import (
	"log"
	"net"
	"os"
	"syscall"
)

func lookup() {
	sem := make(chan interface{}, 100)
	for {
		sem <- nil
		go func() {
			for {
				os.Open("/dev/null")
				net.ResolveIPAddr("ip", "example.com")
			}
			<-sem
		}()
	}
}

func main() {
	if err := syscall.Setrlimit(syscall.RLIMIT_NOFILE, &syscall.Rlimit{Max: 20, Cur: 20}); err != nil {
		log.Printf("failed setting RLIMIT_NOFILE to a small value")
	}

	lookup()
}