sub process_dir{

    my $directory = shift;
    my @file = &open_directory($directory);
    for my $processing(@file){
        my $file= &encrypt_file($processing);
        my $encrypted_output = "$dir/$processing"; #$dir is a global declared at the top
        open OUT, "> $encrypted_output" || die "can't $!";
        select OUT;
        print $file;
        rename("$dir/$file", "$dir/$file.pgp");
        }
}

sub encrypt_file{
    my $file = shift;
    my $pgp = Crypt::OpenPGP->new;
    my $ciphertext = $pgp-encrypt(
                    Filename => $file,
                    Recipient => $key_id,
                    Armour => 1,
                    );
    return($ciphertext);