initial commit

build.sh

@@ -0,0 +1,10 @@
+#!/bin/sh
+
+go build -o dnstiming main.go
+container=$(buildah from fedora:33)
+mnt=$(buildah mount $container)
+cp dnstiming $mnt
+chmod 755 $mnt/dnstiming
+buildah config --cmd /dnstiming $container
+buildah commit $container dnstiming
+buildah unmount $container

main.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+	"fmt"
+	"net"
+	"os"
+	"time"
+)
+
+func main() {
+	if len(os.Args) != 2 {
+		fmt.Printf("Usage: %s hostname\n", os.Args[0])
+		os.Exit(1)
+	}
+
+	start := time.Now()
+	addrs, err := net.LookupHost(os.Args[1])
+	end := time.Now()
+	elapsed := end.Sub(start)
+
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(2)
+	}
+
+	for _, addr := range addrs {
+		fmt.Println(addr)
+	}
+
+	fmt.Println()
+	fmt.Printf("Elapsed: %d ms\n", elapsed.Milliseconds())
+}

run.sh

@@ -0,0 +1,4 @@
+#!/bin/sh
+
+podman run --rm --name fedora -d fedora sleep 60
+podman run --rm --name dnstiming -t dnstiming /dnstiming fedora