2 problems with AnyEvent::DNS

Михаил Монашёв softsearch at gmail.com
Wed Jul 9 16:44:10 CEST 2008

Hi, Marc Lehmann.


1. I create object AnyEvent::DNS:

     my $resolver = AnyEvent::DNS->new()

2. Resolve some hosts.

2. Fetch some urls asynchronously if it's host has been resolved.

3. remove AnyEvent::DNS object:

   undef $resolver;

4. I create new object AnyEvent::DNS. Resolve some host. And get
problem: some old watchers rise and run old callback function in new

Old watchers wasn't removed after "undef $resolver;" and continue
working. Why? Timeout dosn't work correctly in AnyEvent::DNS I think.
It dosn't remove watchers.

#! /usr/bin/perl
use strict;
use warnings;

use AnyEvent::DNS;

my $resolver = AnyEvent::DNS->new(timeout => [2], server =>
my $cv = AnyEvent->condvar();
my $resolve_sub = sub {
    warn "mindmix.ru resolved\n";
$resolver->resolve('mindmix.ru', 'a', accept => ["a"], $resolve_sub);
my $timer = AnyEvent->timer(
    after => 1,
    cb => sub {
        warn "timeout for mindmix.ru\n";

undef $timer;
undef $resolver; # here all watchers have to remove
undef $resolve_sub;
undef $cv;

$resolver = AnyEvent::DNS->new(timeout => [2], server =>
$cv = AnyEvent->condvar();
my $resolve_sub2 = sub {
    warn "beon.ru resolved\n";
$resolver->resolve('google.com', 'a', accept => ["a"], $resolve_sub2);
$timer = AnyEvent->timer(
    after => 3,
    cb => sub {
        warn "timeout for beon.ru\n";


timeout for mindmix.ru
mindmix.ru resolved
beon.ru resolved
timeout for beon.ru

Why "mindmix.ru resolved" appear after "undef $resolver;" ?


Also some memory leaks found. Just add

use Devel::Leak::Object qw(GLOBAL_bless);

and run script:

Tracked objects by class:
AnyEvent::DNS                            1
Config                                   1
Errno                                    1


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