NAME

       Mail::SpamAssassin::RegistryBoundaries - domain delegation rules

METHODS

       ($hostname, $domain) = split_domain ($fqdn)
           Cut a fully-qualified hostname into the hostname part and the domain part, splitting
           at the DNS registry boundary.

           Examples:

               "www.foo.com" => ( "www", "foo.com" )
               "www.foo.co.uk" => ( "www", "foo.co.uk" )

       $domain = trim_domain($fqdn)
           Cut a fully-qualified hostname into the hostname part and the domain part, returning
           just the domain.

           Examples:

               "www.foo.com" => "foo.com"
               "www.foo.co.uk" => "foo.co.uk"

       $ok = is_domain_valid($dom)
           Return 1 if the domain is valid, "undef" otherwise.  A valid domain (a) does not
           contain whitespace, (b) contains at least one dot, and (c) uses a valid TLD or ccTLD.