14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<!DOCTYPE book [
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<!ENTITY mdash "&#8212;">]>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<!--
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews - Copyright (C) 2001, 2004, 2005, 2007, 2014-2016 Internet Systems Consortium, Inc. ("ISC")
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson -
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews - This Source Code Form is subject to the terms of the Mozilla Public
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews - License, v. 2.0. If a copy of the MPL was not distributed with this
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews - file, You can obtain one at http://mozilla.org/MPL/2.0/.
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson-->
19c7b1a0293498a3e36692c59646ed6e15ffc8d0Tinderbox User
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<!-- Converted by db4-upgrade version 1.0 -->
83a28ca274521e15086fc39febde507bcc4e145eMark Andrews<refentry xmlns:db="http://docbook.org/ns/docbook" version="5.0">
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <info>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <date>2007-06-18</date>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt </info>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refentryinfo>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <corpname>ISC</corpname>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <corpauthor>Internet Systems Consortium, Inc.</corpauthor>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </refentryinfo>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refmeta>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refentrytitle>lwres_gethostent</refentrytitle>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <manvolnum>3</manvolnum>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refmiscinfo>BIND9</refmiscinfo>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </refmeta>
86b0285d7e65601645db4090d62ee6cb63abad6cAndreas Gustafsson
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <docinfo>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <copyright>
194e2dfffa6a167b8eef0ad11864026b423a1c30Mark Andrews <year>2001</year>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <year>2004</year>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <year>2005</year>
c1a883f2e04d94e99c433b1f6cfd0c0338f4ed85Mark Andrews <year>2007</year>
938440694b33cd752e9e4b71a526368b4811c177Tinderbox User <year>2014</year>
19c7b1a0293498a3e36692c59646ed6e15ffc8d0Tinderbox User <year>2015</year>
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews <year>2016</year>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <holder>Internet Systems Consortium, Inc. ("ISC")</holder>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </copyright>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </docinfo>
86b0285d7e65601645db4090d62ee6cb63abad6cAndreas Gustafsson
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refnamediv>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refname>lwres_gethostbyname</refname>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refname>lwres_gethostbyname2</refname>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refname>lwres_gethostbyaddr</refname>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refname>lwres_gethostent</refname>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refname>lwres_sethostent</refname>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refname>lwres_endhostent</refname>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refname>lwres_gethostbyname_r</refname>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refname>lwres_gethostbyaddr_r</refname>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refname>lwres_gethostent_r</refname>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refname>lwres_sethostent_r</refname>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refname>lwres_endhostent_r</refname>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refpurpose>lightweight resolver get network host entry</refpurpose>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </refnamediv>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refsynopsisdiv>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcsynopsis>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcsynopsisinfo>#include &lt;lwres/netdb.h&gt;</funcsynopsisinfo>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcprototype>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcdef>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafssonstruct hostent *
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<function>lwres_gethostbyname</function></funcdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>const char *<parameter>name</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </funcprototype>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcprototype>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcdef>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafssonstruct hostent *
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<function>lwres_gethostbyname2</function></funcdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>const char *<parameter>name</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int <parameter>af</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </funcprototype>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcprototype>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcdef>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafssonstruct hostent *
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<function>lwres_gethostbyaddr</function></funcdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>const char *<parameter>addr</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int <parameter>len</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int <parameter>type</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </funcprototype>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcprototype>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcdef>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafssonstruct hostent *
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<function>lwres_gethostent</function></funcdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>void</paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </funcprototype>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcprototype>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcdef>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafssonvoid
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<function>lwres_sethostent</function></funcdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int <parameter>stayopen</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </funcprototype>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcprototype>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcdef>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafssonvoid
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<function>lwres_endhostent</function></funcdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>void</paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </funcprototype>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcprototype>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcdef>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafssonstruct hostent *
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<function>lwres_gethostbyname_r</function></funcdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>const char *<parameter>name</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>struct hostent *<parameter>resbuf</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>char *<parameter>buf</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int <parameter>buflen</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int *<parameter>error</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </funcprototype>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcprototype>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcdef>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafssonstruct hostent *
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<function>lwres_gethostbyaddr_r</function></funcdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>const char *<parameter>addr</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int <parameter>len</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int <parameter>type</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>struct hostent *<parameter>resbuf</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>char *<parameter>buf</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int <parameter>buflen</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int *<parameter>error</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </funcprototype>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcprototype>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcdef>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafssonstruct hostent *
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<function>lwres_gethostent_r</function></funcdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>struct hostent *<parameter>resbuf</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>char *<parameter>buf</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int <parameter>buflen</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int *<parameter>error</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </funcprototype>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcprototype>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcdef>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafssonvoid
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<function>lwres_sethostent_r</function></funcdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>int <parameter>stayopen</parameter></paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </funcprototype>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<funcprototype>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <funcdef>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafssonvoid
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson<function>lwres_endhostent_r</function></funcdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <paramdef>void</paramdef>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </funcprototype>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson</funcsynopsis>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </refsynopsisdiv>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <refsection><info><title>DESCRIPTION</title></info>
30eec077db2bdcb6f2a0dc388a3cdde2ede75ec1Mark Andrews
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein These functions provide hostname-to-address and
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein address-to-hostname lookups by means of the lightweight resolver.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein They are similar to the standard
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <citerefentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refentrytitle>gethostent</refentrytitle><manvolnum>3</manvolnum>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </citerefentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein functions provided by most operating systems.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein They use a
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>struct hostent</type>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein which is usually defined in
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <filename>&lt;namedb.h&gt;</filename>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para><programlisting>
8eea877894ea5bcf5cdd9ca124a8601ad421d753Andreas Gustafssonstruct hostent {
8eea877894ea5bcf5cdd9ca124a8601ad421d753Andreas Gustafsson char *h_name; /* official name of host */
8eea877894ea5bcf5cdd9ca124a8601ad421d753Andreas Gustafsson char **h_aliases; /* alias list */
8eea877894ea5bcf5cdd9ca124a8601ad421d753Andreas Gustafsson int h_addrtype; /* host address type */
8eea877894ea5bcf5cdd9ca124a8601ad421d753Andreas Gustafsson int h_length; /* length of address */
8eea877894ea5bcf5cdd9ca124a8601ad421d753Andreas Gustafsson char **h_addr_list; /* list of addresses from name server */
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson};
8eea877894ea5bcf5cdd9ca124a8601ad421d753Andreas Gustafsson#define h_addr h_addr_list[0] /* address, for backward compatibility */
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson</programlisting>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein The members of this structure are:
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <variablelist>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <term><constant>h_name</constant></term>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein The official (canonical) name of the host.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <term><constant>h_aliases</constant></term>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein A NULL-terminated array of alternate names (nicknames) for the
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein host.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <term><constant>h_addrtype</constant></term>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein The type of address being returned &mdash;
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>PF_INET</type>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein or
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>PF_INET6</type>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <term><constant>h_length</constant></term>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein The length of the address in bytes.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <term><constant>h_addr_list</constant></term>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein A <type>NULL</type>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein terminated array of network addresses for the host.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein Host addresses are returned in network byte order.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </variablelist>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein For backward compatibility with very old software,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <constant>h_addr</constant>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein is the first address in
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <constant>h_addr_list.</constant>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para><function>lwres_gethostent()</function>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_sethostent()</function>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_endhostent()</function>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostent_r()</function>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_sethostent_r()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein and
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_endhostent_r()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein provide iteration over the known host entries on systems that
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein provide such functionality through facilities like
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <filename>/etc/hosts</filename>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein or NIS. The lightweight resolver does not currently implement
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein these functions; it only provides them as stub functions that always
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein return failure.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
86b0285d7e65601645db4090d62ee6cb63abad6cAndreas Gustafsson
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para><function>lwres_gethostbyname()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein and <function>lwres_gethostbyname2()</function> look up the
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein hostname <parameter>name</parameter>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyname()</function> always looks for an
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein IPv4 address while <function>lwres_gethostbyname2()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein looks for an address of protocol family
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>af</parameter>: either <type>PF_INET</type> or
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>PF_INET6</type> &mdash; IPv4 or IPV6 addresses
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein respectively. Successful calls of the functions return a
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>struct hostent</type>for the name that was looked up.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>NULL</type> is returned if the lookups by
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyname()</function> or
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyname2()</function> fail.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
86b0285d7e65601645db4090d62ee6cb63abad6cAndreas Gustafsson
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein Reverse lookups of addresses are performed by
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyaddr()</function>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>addr</parameter> is an address of length
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>len</parameter> bytes and protocol family
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>type</parameter> &mdash; <type>PF_INET</type> or
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>PF_INET6</type>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyname_r()</function> is a
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein thread-safe function
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein for forward lookups. If an error occurs, an error code is returned in
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>*error</parameter>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>resbuf</parameter> is a pointer to a
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>struct hostent</type> which is initialised by a successful call to
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyname_r()</function>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>buf</parameter> is a buffer of length
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>len</parameter> bytes which is used to store the
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <constant>h_name</constant>, <constant>h_aliases</constant>, and
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <constant>h_addr_list</constant> elements of the
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>struct hostent</type> returned in <parameter>resbuf</parameter>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein Successful calls to <function>lwres_gethostbyname_r()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein return <parameter>resbuf</parameter>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein which is a pointer to the <type>struct hostent</type> it created.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para><function>lwres_gethostbyaddr_r()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein is a thread-safe function
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein that performs a reverse lookup of address <parameter>addr</parameter>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein which is <parameter>len</parameter> bytes long and is of
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein protocol
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein family <parameter>type</parameter> &mdash; <type>PF_INET</type> or
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>PF_INET6</type>. If an error occurs, the error code is returned
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein in <parameter>*error</parameter>. The other function
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein parameters are
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein identical to those in <function>lwres_gethostbyname_r()</function>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>resbuf</parameter> is a pointer to a
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>struct hostent</type> which is initialised by a successful call to
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyaddr_r()</function>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>buf</parameter> is a buffer of length
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>len</parameter> bytes which is used to store the
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <constant>h_name</constant>, <constant>h_aliases</constant>, and
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <constant>h_addr_list</constant> elements of the
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>struct hostent</type> returned in <parameter>resbuf</parameter>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein Successful calls to <function>lwres_gethostbyaddr_r()</function> return
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>resbuf</parameter>, which is a pointer to the
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>struct hostent()</function> it created.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
86b0285d7e65601645db4090d62ee6cb63abad6cAndreas Gustafsson
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt </refsection>
86b0285d7e65601645db4090d62ee6cb63abad6cAndreas Gustafsson
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <refsection><info><title>RETURN VALUES</title></info>
30eec077db2bdcb6f2a0dc388a3cdde2ede75ec1Mark Andrews
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein The functions
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyname()</function>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyname2()</function>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyaddr()</function>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein and
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostent()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein return NULL to indicate an error. In this case the global variable
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>lwres_h_errno</type>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein will contain one of the following error codes defined in
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <filename>&lt;lwres/netdb.h&gt;</filename>:
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <variablelist>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <term><constant>HOST_NOT_FOUND</constant></term>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein The host or address was not found.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <term><constant>TRY_AGAIN</constant></term>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein A recoverable error occurred, e.g., a timeout.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein Retrying the lookup may succeed.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <term><constant>NO_RECOVERY</constant></term>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein A non-recoverable error occurred.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <term><constant>NO_DATA</constant></term>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein The name exists, but has no address information
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein associated with it (or vice versa in the case
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein of a reverse lookup). The code NO_ADDRESS
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein is accepted as a synonym for NO_DATA for backwards
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein compatibility.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </listitem>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </varlistentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </variablelist>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
86b0285d7e65601645db4090d62ee6cb63abad6cAndreas Gustafsson
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para><citerefentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refentrytitle>lwres_hstrerror</refentrytitle><manvolnum>3</manvolnum>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </citerefentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein translates these error codes to suitable error messages.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
86b0285d7e65601645db4090d62ee6cb63abad6cAndreas Gustafsson
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para><function>lwres_gethostent()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein and <function>lwres_gethostent_r()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein always return <type>NULL</type>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein Successful calls to <function>lwres_gethostbyname_r()</function> and
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyaddr_r()</function> return
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <parameter>resbuf</parameter>, a pointer to the
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>struct hostent</type> that was initialised by these functions. They return
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>NULL</type> if the lookups fail or if <parameter>buf</parameter>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein was too small to hold the list of addresses and names referenced by
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein the <constant>h_name</constant>, <constant>h_aliases</constant>, and
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <constant>h_addr_list</constant> elements of the
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>struct hostent</type>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein If <parameter>buf</parameter> was too small, both
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyname_r()</function> and
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyaddr_r()</function> set the global
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein variable
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>errno</type> to <errorcode>ERANGE</errorcode>.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
86b0285d7e65601645db4090d62ee6cb63abad6cAndreas Gustafsson
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt </refsection>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <refsection><info><title>SEE ALSO</title></info>
30eec077db2bdcb6f2a0dc388a3cdde2ede75ec1Mark Andrews
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para><citerefentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refentrytitle>gethostent</refentrytitle><manvolnum>3</manvolnum>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </citerefentry>,
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <citerefentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refentrytitle>lwres_getipnode</refentrytitle><manvolnum>3</manvolnum>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </citerefentry>,
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <citerefentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <refentrytitle>lwres_hstrerror</refentrytitle><manvolnum>3</manvolnum>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </citerefentry>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt </refsection>
ddccd5811feff696ba460dabfb666ce61040f545Andreas Gustafsson
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <refsection><info><title>BUGS</title></info>
30eec077db2bdcb6f2a0dc388a3cdde2ede75ec1Mark Andrews
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para><function>lwres_gethostbyname()</function>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyname2()</function>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyaddr()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein and
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_endhostent()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein are not thread safe; they return pointers to static data and
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein provide error codes through a global variable.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein Thread-safe versions for name and address lookup are provided by
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyname_r()</function>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein and
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <function>lwres_gethostbyaddr_r()</function>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein respectively.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <para>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein The resolver daemon does not currently support any non-DNS
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein name services such as
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <filename>/etc/hosts</filename>
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein or
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein <type>NIS</type>,
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein consequently the above functions don't, either.
268a4475065fe6a8cd7cc707820982cf5e98f430Rob Austein </para>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt </refsection>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt</refentry>