#!/usr/bin/perl -w
use strict;
use File::Copy;

my $new="mytest";
open NEW, ">$new" or die "I can not open file to write: $!\n";

print NEW "this is a test";

close NEW;

copy ("$new", "$new.new") or die "can't make a copy: $!\n";

unlink $new or die "can not unlink it: $!\n";

rename ("$new.new", "$new") or die "cant move it: $!\n";

unlink $new or die "can not unlink it at the end: $!\n";