#!/usr/bin/perl
use strict;
use warnings;
use Tie::File;
use Sensitive_Array;

# this is the global var I am using
$main::touched=0;
my (@array, @watched_array);
my $file='test_tie_file';

# First tie the array to the file
tie @array, 'Tie::File', $file or die "cannot tie to $file: $!\n";
push @array, int (rand 1000) until $#array > 39; # fill it on the first pass

# now tie it up to an array that will tell us when it was altered
tie @watched_array, 'Sensitive_Array', \@array;

print "array of length $#watched_array is now watched\n";

print "would you like to alter the file (y/n)\n";
my $ansa=<STDIN>;
push @watched_array, 'touched' if $ansa =~/^y/;

untie @array;

if ($main::touched) {
    print "File has been altered\n"
} else {
    print "File remains the same\n";
}