Net::DNS::RR(3pm)              User Contributed Perl Documentation              Net::DNS::RR(3pm)



NAME
       Net::DNS::RR - DNS resource record base class

SYNOPSIS
           use Net::DNS;

           $rr = new Net::DNS::RR('example.com IN A 192.0.2.99');

           $rr = new Net::DNS::RR(
                   name    => 'example.com',
                   type    => 'A',
                   address => '192.0.2.99'
                   );

DESCRIPTION
       Net::DNS::RR is the base class for DNS Resource Record (RR) objects.  See also the manual
       pages for each specific RR type.

METHODS
       WARNING!!!  Do not assume the RR objects you receive from a query are of a particular type
       -- you must always check the object type before calling any of its methods.  If you call
       an unknown method, you will get an error message and execution will be terminated.

   new (from string)
           $a     = new Net::DNS::RR('host.example.com. 86400 A 192.0.2.1');
           $mx    = new Net::DNS::RR('example.com. 7200 MX 10 mailhost.example.com.');
           $cname = new Net::DNS::RR('www.example.com 300 IN CNAME host.example.com');
           $txt   = new Net::DNS::RR('txt.example.com 3600 HS TXT "text data"');

       Returns an RR object of the appropriate type, or a "Net::DNS::RR" object if the type is
       not implemented.   The attribute values are extracted from the string passed by the user.
       The syntax of the argument string follows the RFC1035 specification for zone files, and is
       compatible with the result returned by the string method.

       The name and RR type are required; all other information is optional.  If omitted, the TTL
       defaults to 0 and the RR class defaults to IN.  Omitting the optional fields is useful for
       creating the empty RDATA sections required for certain dynamic update operations.  See the
       "Net::DNS::Update" manual page for additional examples.

       All names are interpreted as fully qualified domain names.  The trailing dot (.) is
       optional.

   new (from hash)
           $rr = new Net::DNS::RR(
                   name    => 'host.example.com',
                   ttl     => 86400,
                   class   => 'IN',
                   type    => 'A',
                   address => '192.0.2.1'
                   );

           $rr = new Net::DNS::RR(
                   name    => 'txt.example.com',
                   type    => 'TXT',
                   txtdata => [ 'one', 'two' ]
                   );

       Returns an RR object of the appropriate type, or a "Net::DNS::RR" object if the type is
       not implemented.   See the manual pages for each RR type to see what fields the type
       requires.

       The "name" and "type" fields are required; all others are optional.  If omitted, "ttl"
       defaults to 0 and "class" defaults to IN.  Omitting the optional fields is useful for
       creating the empty RDATA sections required for certain dynamic update operations.

   decode
           ( $rr, $next ) = decode Net::DNS::RR( \$data, $offset, @opaque );

       Decodes a DNS resource record at the specified location within a DNS packet.

       The argument list consists of a reference to the buffer containing the packet data and
       offset indicating where resource record begins.  Remaining arguments, if any, are passed
       as opaque data to subordinate decoders.

       Returns a "Net::DNS::RR" object and the offset of the next record in the packet.

       An exception is raised if the data buffer contains insufficient or corrupt data.

       Any remaining arguments are passed as opaque data to subordinate decoders and do not form
       part of the published interface.

   encode
           $data = $rr->encode( $offset, @opaque );

       Returns the "Net::DNS::RR" in binary format suitable for inclusion in a DNS packet buffer.

       The offset indicates the intended location within the packet data where the "Net::DNS::RR"
       is to be stored.

       Any remaining arguments are opaque data which are passed intact to subordinate encoders.

   canonical
           $data = $rr->canonical;

       Returns the "Net::DNS::RR" in canonical binary format suitable for DNSSEC signature
       validation.

       The absence of the associative array argument signals to subordinate encoders that the
       canonical uncompressed lower case form of embedded domain names is to be used.

   print
           $rr->print;

       Prints the record to the standard output.  Calls the string method to get the RR string
       representation.

   string
           print $rr->string, "\n";

       Returns a string representation of the RR using the zone file format described in RFC1035.
       All domain names are fully qualified with trailing dot.  This differs from RR attribute
       methods, which omit the trailing dot.

   owner name
           $owner = $rr->name;

       Returns the owner name of the record.

   type
           $type = $rr->type;

       Returns the record type.

   class
           $class = $rr->class;

       Resource record class.

   ttl
           $ttl = $rr->ttl;
           $ttl = $rr->ttl(3600);

       Resource record time to live in seconds.

   rdata
           $rr = new Net::DNS::RR( type => NULL, rdata => 'arbitrary' );

       Resource record data section when viewed as opaque octets.

   rdstring
           $rdstring = $rr->rdstring;

       Returns a string representation of the RR-specific data.

   plain
           $plain = $rr->plain;

       Returns a simplified single line representation of the RR using the zone file format
       defined in RFC1035.  This facilitates interaction with programs like nsupdate which have
       simplified RR parsers.

   token
           @token = $rr->token;

       Returns a token list representation of the RR zone file string.

Sorting of RR arrays
       Sorting of RR arrays is done by Net::DNS::rrsort(), see documentation for Net::DNS. This
       package provides class methods to set the comparator function used for a particular RR
       based on its attributes.

   set_rrsort_func
           Net::DNS::RR::MX->set_rrsort_func(
               'preference',
               sub { $Net::DNS::a->preference <=> $Net::DNS::b->preference }
               );

           Net::DNS::RR::MX->set_rrsort_func(
               'default_sort',
               Net::DNS::RR::MX->get_rrsort_func('preference')
               );

       set_rrsort_func() must be called as a class method. The first argument is the attribute
       name on which the sorting is to take place. If you specify "default_sort" then that is the
       sort algorithm that will be used when rrsort() is called without an RR attribute as
       argument.

       The second argument is a reference to a comparison function that uses the global variables
       $a and $b in the Net::DNS package. During sorting, the variables $a and $b will contain
       references to objects of the class whose set_rrsort_func() was called. The above sorting
       function will only be applied to Net::DNS::RR::MX objects.

       The above example is the sorting function implemented in MX.

COPYRIGHT
       Copyright (c)1997-2002 Michael Fuhr.

       Portions Copyright (c)2002-2004 Chris Reinhardt.

       Portions Copyright (c)2005-2007 Olaf Kolkman.

       Portions Copyright (c)2007,2012 Dick Franks.

       All rights reserved.

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

SEE ALSO
       perl, Net::DNS, Net::DNS::Question, Net::DNS::Packet, Net::DNS::Update, RFC1035 Section
       4.1.3, RFC1123, RFC3597



perl v5.20.2                                2014-10-29                          Net::DNS::RR(3pm)