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

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

	use Net::hostent;

       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.

	use Net::hostent;
	use Socket;

	@ARGV =	('') unless	@ARGV;

	for $host ( @ARGV ) {

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

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

	   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;

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

       Tom Christiansen

perl v5.26.0			  2017-02-28		       Net::hostent(3)


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