Net::hostent(3perl)              Perl Programmers Reference Guide             Net::hostent(3perl)



NAME
       Net::hostent - by-name interface to Perl's built-in gethost*() functions

SYNOPSIS
        use Net::hostent;

DESCRIPTION
       This module's default exports override the core gethostbyname() and gethostbyaddr()
       functions, replacing them with versions that return "Net::hostent" objects.  This object
       has methods that return the similarly named structure field name from the C's hostent
       structure from netdb.h; namely name, aliases, addrtype, length, and addr_list.  The
       aliases and addr_list methods return array reference, the rest scalars.  The addr method
       is equivalent to the zeroth element in the addr_list array reference.

       You may also import all the structure fields directly into your namespace as regular
       variables using the :FIELDS import tag.  (Note that this still overrides your core
       functions.)  Access these fields as variables named with a preceding "h_".  Thus,
       "$host_obj->name()" corresponds to $h_name if you import the fields.  Array references are
       available as regular array variables, so for example "@{ $host_obj->aliases() }" would be
       simply @h_aliases.

       The gethost() function is a simple front-end that forwards a numeric argument to
       gethostbyaddr() by way of Socket::inet_aton, and the rest to gethostbyname().

       To access this functionality without the core overrides, pass the "use" an empty import
       list, and then access function functions with their full qualified names.  On the other
       hand, the built-ins are still available via the "CORE::" pseudo-package.

EXAMPLES
        use Net::hostent;
        use Socket;

        @ARGV = ('netscape.com') unless @ARGV;

        for $host ( @ARGV ) {

           unless ($h = gethost($host)) {
               warn "$0: no such host: $host\n";
               next;
           }

           printf "\n%s is %s%s\n",
                   $host,
                   lc($h->name) eq lc($host) ? "" : "*really* ",
                   $h->name;

           print "\taliases are ", join(", ", @{$h->aliases}), "\n"
                       if @{$h->aliases};

           if ( @{$h->addr_list} > 1 ) {
               my $i;
               for $addr ( @{$h->addr_list} ) {
                   printf "\taddr #%d is [%s]\n", $i++, inet_ntoa($addr);
               }
           } else {
               printf "\taddress is [%s]\n", inet_ntoa($h->addr);
           }

           if ($h = gethostbyaddr($h->addr)) {
               if (lc($h->name) ne lc($host)) {
                   printf "\tThat addr reverses to host %s!\n", $h->name;
                   $host = $h->name;
                   redo;
               }
           }
        }

NOTE
       While this class is currently implemented using the Class::Struct module to build a
       struct-like class, you shouldn't rely upon this.

AUTHOR
       Tom Christiansen



perl v5.20.2                                2014-12-27                        Net::hostent(3perl)