I have a problem - the code within the function works ok. I know this because I can call the function with
$input="1.1.1.1";
&dnslookup;

What doesn't work though is if I try to step through the array and call the function.

I end up getting the following error message Can't call method "answer" on an undefined value at ./dns.pl line 10.

Is anybody out there able to help me pick my silly mistake? (it's late in the afternoon here)


#!/usr/bin/perl
use Net::DNS::Resolver;
use Thread::Pool;

sub dnslookup {
my $res=Net::DNS::Resolver->new;

my $search = $res->search($input);

foreach $rr ($search->answer)
{
        my $type=$rr->type;
        if ($type eq "A")
        {
                $host=$rr->address;
        }
        if ($type eq "PTR")
        {
                $host=$rr->ptrdname;
        }
        if ($type eq "CNAME")
        {
                $host=$rr->cname;
        }
}

print "$host\t$input\n";
}


open (FILE, "./foo") || die "Could not open file\n";
@ip=<FILE>;
close (FILE);



foreach (@ip) {
        $input=$_;
        print $input;
        &dnslookup;
}

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In reply to Net::DNS looping help by svankalken

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