Hi, I've been trying to get parallel DNS working with AnyEvent::DNS. My first poor attempt is effectively the same as synchronous DNS because the program waits for the reply before moving on the next iteration of the loop: 

#!/usr/bin/perl -w
use strict;
use warnings;
use AnyEvent::DNS;

my ($domain);
my (@domains,@condvars);

my $resolver = AnyEvent::DNS::resolver;

while ($domain = <>;)
{
  # clean off newline
  chomp $domain;
  
  # send dns packets
  $resolver->resolve($domain,"*",my $condvar  = AnyEvent->condvar);

  # receive dns packets
  $condvar->recv;
  print "$domain\n";
}

[download]
My second attempt was slightly better in that it can send off ten different DNS packets but receives a reply from the last request ten times (not what I wanted): 

#!/usr/bin/perl -w
use strict;
use warnings;
use AnyEvent::DNS;

my ($domain);
my (@domains,@condvars);

my $resolver = AnyEvent::DNS::resolver;

while (1)
{
  # send dns packets
  for my $i (1..10)
  {
    $domain = <>;
    # clean off newline
    chomp $domain;
    $resolver->resolve($domain,"*",my $condvar  = AnyEvent->condvar);
    push @condvars, $condvar; 
  }
  
  # receive dns packets
  while (my $condvar = pop @condvars)
  {
    $condvar->recv;
    print "$domain\n";
  }
}

[download]
The problem is that $condvar seems to be working like a reference to an object and so each of the 10 $condvars in the stack end up being whatever the last $condvar was. I've tried typeglobbing but this just causes compilation errors. Does anybody know how to do this right?

In reply to AnyEvent::DNS is effectively synchronous? by jc
in thread Async DNS with LWP by jc

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