sub get_first_line {
    my ($filename) = @_;

    open my $fh, '<', $filename
        or die "Cannot open '$filename' for reading: $!\n";
    return scalar <$fh>;
}

use File::ReadBackwards;
sub get_last_line {
    my ($filename) = @_;

    my $fh = File::ReadBackwards->new( $filename )
        or die "Cannot open '$filename' for reading backwards: $!\n";

    return $fh->readline;
}