use IO::Select qw( );

# How long (in seconds) of not getting anything is considered done.
use constant TIMEOUT => 2.0;

open(my $pipe, '-|', 'mDNS -L "Service Name" _service._tcp domain');
my $buf = '';

# Wait to get something.
my $rv = sysread($pipe, $buf, 64*1024, length($buf));
die $! if !defined($rv);

# Wait until we stop getting
if ($rv) {
   my $sel = IO::Select->new($pipe);
   for (;;) {
      if (!$sel->can_read(TIMEOUT)) {
         kill KILL => $pid;
         last;
      }

      my $rv = sysread($pipe, $buf, 64*1024, length($buf));
      die $! if !defined($rv);
      last if !$rv;
   }
}

close($pipe);

print("Got:\n$buf\n");