net::hostent(3pm) [redhat man page]

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

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()" corre-
       sponds 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
";
	       next;
	   }

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

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

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

	   if ($h = gethostbyaddr($h->addr)) {
	       if (lc($h->name) ne lc($host)) {
		   printf "	That addr reverses to host %s!
", $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 v5.8.0							    2002-06-01							 Net::hostent(3pm)