#!/home/ben/software/install/bin/perl
use warnings;
use strict;
use utf8;
use File::Slurper qw/read_binary write_binary/;
my $filea = "$0";
my $text = read_binary ($filea);
my $fileb = "$filea-copy";
if (-f $fileb) {
    unlink $fileb or die $!;
}
write_binary ($fileb, $text);
my $permissionsa = (stat ($filea))[2];
my $permissionsb = (stat ($fileb))[2];
printf ("A: %s - %o\n", $filea, $permissionsa);
printf ("B before: %s - %o\n", $fileb, $permissionsb);
chmod $permissionsa, $fileb or die $!;
$permissionsb = (stat ($fileb))[2];
printf ("B after: %s - %o\n", $fileb, $permissionsb);