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



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 RR type.

METHODS
       WARNING!!!  Do not assume the RR objects you receive from a query are of a particular type -- 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     = Net::DNS::RR->new("foo.example.com. 86400 A 10.1.2.3");
        $mx    = Net::DNS::RR->new("example.com. 7200 MX 10 mailhost.example.com.");
        $cname = Net::DNS::RR->new("www.example.com 300 IN CNAME www1.example.com");
        $txt   = Net::DNS::RR->new('baz.example.com 3600 HS TXT "text record"');

       Returns a "Net::DNS::RR" object of the appropriate type and initialized from the string passed by the
       user.  The format of the string is that used in zone files, and is compatible with the string
       returned by "Net::DNS::RR->string".

       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 must be fully qualified.  The trailing dot (.) is optional.

   new (from hash)
        $rr = Net::DNS::RR->new(
                name    => "foo.example.com",
                ttl     => 86400,
                class   => "IN",
                type    => "A",
                address => "10.1.2.3",
        );

        $rr = Net::DNS::RR->new(
                name => "foo.example.com",
                type => "A",
        );

       Returns an RR object of the appropriate type, or a "Net::DNS::RR" object if the type isn't
       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.

       The fields are case-insensitive, but starting each with uppercase is recommended.

   decode
           ($rrobj, $offset) = Net::DNS::RR->decode(\$data, $offset);

       Decodes a DNS resource record at the specified location within a DNS packet.  The first argument is a
       reference to the packet data.  The second argument is the offset within the packet where the resource
       record begins.

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

       Decoding is aborted if the object could not be created (e.g., corrupt or insufficient data).

   print
           $rr->print;

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

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

       Returns a string representation of the RR.  Calls the rdatastr method to get the RR-specific data.
       Domain names arereturned in RFC1035 format, i.e. all non letter, digit, hyphen characters are
       represented as \DDD. Besides, all domain names are expanded to fully qualified domain names, with
       trailing dot.  This is in contrast to accessor methods of individual data elements in RR objects,
       like name, which will not return the trailing dot.

   rdatastr
           $s = $rr->rdatastr;

       Returns a string containing RR-specific data.  Subclasses will need to implement this method.

   name
           $name = $rr->name;

       Returns the record's domain name.

   type
           $type = $rr->type;

       Returns the record's type.

   class
           $class = $rr->class;

       Returns the record's class.

   ttl
           $ttl = $rr->ttl;

       Returns the record's time-to-live (TTL).

   rdlength
           $rdlength = $rr->rdlength;

       Returns the length of the record's data section.

   rdata
           $rdata = $rr->rdata

       Returns the record's data section as binary data.

Sorting of RR arrays
       As of version 0.55 there is functionality to help you sort RR arrays. The sorting is done by
       Net::DNS::rrsort(), see the Net::DNS documentation. This package provides class methods to set the
       sorting functions used for a particular RR based on a particular attribute.

   set_rrsort_func
       Net::DNS::RR::SRV->set_rrsort_func("priority",                       sub {                        my
       ($a,$b)=($Net::DNS::a,$Net::DNS::b);                        $a->priority <=> $b->priority
                              ||                        $b->weight <=> $a->weight
                            }

       Net::DNS::RR::SRV->set_rrsort_func("default_sort",                       sub {
       my ($a,$b)=($Net::DNS::a,$Net::DNS::b);                        $a->priority <=> $b->priority
                              ||                        $b->weight <=> $a->weight
                            }

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

       The second argument is a reference to a function that uses the variables $a and $b global to the
       "from Net::DNS"(!!)package for the sorting. During the sorting $a and $b will contain references to
       objects from the class you called the set_prop_sort from. In other words, you can rest assured that
       the above sorting function will only get Net::DNS::RR::SRV objects.

       The above example is the sorting function that actually is implemented in SRV.

BUGS
       This version of "Net::DNS::RR" does little sanity checking on user-created RR objects.

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 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.

       EDNS0 extensions by Olaf Kolkman.

SEE ALSO
       perl, Net::DNS, Net::DNS::Resolver, Net::DNS::Packet, Net::DNS::Update, Net::DNS::Header,
       Net::DNS::Question, RFC 1035 Section 4.1.3



perl v5.16.2                                     2012-01-27                                  Net::DNS::RR(3)