net::dns::resolver::recurse(3) [mojave man page]

Net::DNS::Resolver::Recurse(3)				User Contributed Perl Documentation			    Net::DNS::Resolver::Recurse(3)

NAME

       Net::DNS::Resolver::Recurse - Perform recursive dns lookups

SYNOPSIS

	 use Net::DNS::Resolver::Recurse;
	 my $res = Net::DNS::Resolver::Recurse->new;

DESCRIPTION

       This module is a sub class of Net::DNS::Resolver. So the methods for Net::DNS::Resolver still work for this module as well.  There are just
       a couple methods added:

   hints
       Initialize the hint servers.  Recursive queries need a starting name server to work off of. This method takes a list of IP addresses to use
       as the starting servers.  These name servers should be authoritative for the root (.) zone.

	 $res->hints(@ips);

       If no hints are passed, the default nameserver is asked for the hints.  Normally these IPs can be obtained from the following location:

	 ftp://ftp.internic.net/domain/named.root

   recursion_callback
       This method is takes a code reference, which is then invoked each time a packet is received during the recursive lookup.  For example to
       emulate dig's "+trace" function:

	$res->recursion_callback(sub {
	    my $packet = shift;

	    $_->print for $packet->additional;

	    printf(";; Received %d bytes from %s

",
		$packet->answersize,
		$packet->answerfrom
	    );
	});

   query_dorecursion
       This method is much like the normal query() method except it disables the recurse flag in the packet and explicitly performs the recursion.

	 $packet = $res->query_dorecursion( "www.netscape.com.", "A");

IPv6 transport
       If the appropriate IPv6 libraries are installed the recursive resolver will randomly choose between IPv6 and IPv4 addresses of the
       nameservers it encounters during recursion.

       If you want to force IPv4 transport use the force_v4() method. Also see the IPv6 transport notes in the Net::DNS::Resolver documentation.

AUTHOR

       Rob Brown, bbb@cpan.org

SEE ALSO

       Net::DNS::Resolver,

COPYRIGHT

       Copyright (c) 2002, Rob Brown.  All rights reserved.  Portions Copyright (c) 2005, Olaf M Kolkman.

       This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

       $Id: Recurse.pm 1096 2012-12-28 13:35:15Z willem $

perl v5.18.2							    2014-01-16					    Net::DNS::Resolver::Recurse(3)

Mail::DKIM::DNS(3)					User Contributed Perl Documentation					Mail::DKIM::DNS(3)

NAME

       Mail::DKIM::DNS - performs DNS queries for Mail::DKIM

DESCRIPTION

       This is the module that performs DNS queries for Mail::DKIM.

CONFIGURATION

       This module has a couple configuration settings that the caller may want to use to customize the behavior of this module.

   $Mail::DKIM::DNS::TIMEOUT
       This global variable specifies the maximum amount of time (in seconds) to wait for a single DNS query to complete. The default is 10.

   Mail::DKIM::DNS::resolver()
       Use this global subroutine to get or replace the instance of Net::DNS::Resolver that Mail::DKIM uses. If set to undef (the default), then a
       brand new default instance of Net::DNS::Resolver will be created the first time a DNS query is needed.

       You will call this subroutine if you want to specify non-default options to Net::DNS::Resolver, such as different timeouts, or to enable
       use of a persistent socket. For example:

	 # first, construct a custom DNS resolver
	 my $res = Net::DNS::Resolver->new(
			   udp_timeout => 3, tcp_timeout => 3, retry => 2,
			);
	 $res->udppacketsize(1240);
	 $res->persistent_udp(1);

	 # then, tell Mail::DKIM to use this resolver
	 Mail::DKIM::DNS::resolver($res);

   Mail::DKIM::DNS::enable_EDNS0()
       This is a convenience subroutine that will construct an appropriate DNS resolver that uses EDNS0 (Extension mechanisms for DNS) to support
       large DNS replies, and configure Mail::DKIM to use it. (As such, it should NOT be used in conjunction with the resolver() subroutine
       described above.)

	 Mail::DKIM::DNS::enable_EDNS0();

       Use of EDNS0 is recommended, since it reduces the need for falling back to TCP when dealing with large DNS packets. However, it is not
       enabled by default because some Internet firewalls which do deep inspection of packets are not able to process EDNS0-enabled packets. When
       there is a firewall on a path to a DNS resolver, the EDNS0 feature should be specifically tested before enabling.

AUTHOR

       Jason Long, <jlong@messiah.edu>

COPYRIGHT AND LICENSE

       Copyright (C) 2006-2007, 2012-2013 by Messiah College

       This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.6 or,
       at your option, any later version of Perl 5 you may have available.

perl v5.18.2							    2013-02-07							Mail::DKIM::DNS(3)