package main

import (
	"flag"
)

var option = struct {
	knob uint
}{
	knob: 4096,
}

func init() {
	flag.UintVar(&option.knob, "k", option.knob, "somethin' to play with")
}

// fragment for server main
func main() {
	flag.Parse()
	// ...
}

// put in service path
func service() {
	arr := alloc(option.knob)
	lim := len(arr) - 1
	for i := 0; i < lim; i++ {
		arr[i] = uint64(i)
	}
	copy(arr[1:], arr[:lim+1])
}
func alloc(size uint) []uint64 {
	return make([]uint64, size)
}