#! perl
use Modern::Perl;

my %ports;

while (<DATA>)
{
    next unless /^http/;
    my @records = split /\s+/;

    if (exists $ports{$records[2]})
    {
        warn "Attempt to give port $records[2] a second name";
    }
    else
    {
        $ports{$records[2]} = $records[0];
    }
}

say join(' and ', get_listener_name($_)) for 6712, 4516;

sub get_listener_name
{
    my ($port_to_be_checked) = @_;
    my  @results = ('FALSE', 'a1=null');

    if (exists $ports{$port_to_be_checked})
    {
        @results = ('TRUE', 'a1=' . $ports{$port_to_be_checked} . '(listener name)');
    }

    return @results;
}

__DATA__
name ip port 
------------------------------------ 
http-listener-1 * 6712 
http-listener-2 * 8709

##</code><code>##

21:40 >perl 486_SoPW.pl
TRUE and a1=http-listener-1(listener name)
FALSE and a1=null

21:40 >