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RedHat 9 (Linux i386) - man page for net::hostent (redhat section 3pm)

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() func-
       tions, 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 struc-
       ture 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 vari-
       ables 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 regu-
       lar 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 gethost-
       byaddr() 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 v5.8.0				    2002-06-01				Net::hostent(3pm)


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