sub myFunction
{
    my ($first, $second, $third) = @_;
    .....code.....
}

##</code><code>##

use Getopt::Long;
my $HELP;
my $HOSTNAME;

if (@ARGV > 0)
{
        GetOptions('help|?' => \$HELP,
                   'host|hostname|H=s' => \$HOSTNAME
        );
}