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a34684a59b60a4173c25035d0c627ef17e6dc215rpluem [<!ENTITY mdash "&#8212;">]>

5b88c8507d5ef6d0c4cfbc78230294968175b638minfrin

5b88c8507d5ef6d0c4cfbc78230294968175b638minfrin<refentry>

6c3b9cebb551140fbb25d58bae08b539b3802133ylavic

6c3b9cebb551140fbb25d58bae08b539b3802133ylavic <refentryinfo>

6c3b9cebb551140fbb25d58bae08b539b3802133ylavic <date>June 18, 2007</date>

4f29b65ab4b547ad5dbe506e2d0ff5d12ead9247ylavic </refentryinfo>

4f29b65ab4b547ad5dbe506e2d0ff5d12ead9247ylavic

0a0df13b7f1f4f1a74fe295253d89ca3911b301aylavic <refmeta>

0a0df13b7f1f4f1a74fe295253d89ca3911b301aylavic <refentrytitle>lwres_gethostent</refentrytitle>

0a0df13b7f1f4f1a74fe295253d89ca3911b301aylavic <manvolnum>3</manvolnum>

0a0df13b7f1f4f1a74fe295253d89ca3911b301aylavic <refmiscinfo>BIND9</refmiscinfo>

69301145375a889e7e37caf7cc7321ac0f91801erpluem </refmeta>

69301145375a889e7e37caf7cc7321ac0f91801erpluem

69301145375a889e7e37caf7cc7321ac0f91801erpluem <docinfo>

506bfe33206b2fece40ef25f695af39dd4130facjkaluza <copyright>

506bfe33206b2fece40ef25f695af39dd4130facjkaluza <year>2004</year>

506bfe33206b2fece40ef25f695af39dd4130facjkaluza <year>2005</year>

506bfe33206b2fece40ef25f695af39dd4130facjkaluza <year>2007</year>

d58a848a016d401b965111e50ef829e1641f7834minfrin <holder>Internet Systems Consortium, Inc. ("ISC")</holder>

d58a848a016d401b965111e50ef829e1641f7834minfrin </copyright>

d58a848a016d401b965111e50ef829e1641f7834minfrin <copyright>

2e6f4d654c96c98b761fb012fd25c5d5b1558c44sf <year>2001</year>

2e6f4d654c96c98b761fb012fd25c5d5b1558c44sf <holder>Internet Software Consortium.</holder>

2e6f4d654c96c98b761fb012fd25c5d5b1558c44sf </copyright>

17e6c95f3b22d18acdf8380fb26a8d0e10c80767ylavic </docinfo>

17e6c95f3b22d18acdf8380fb26a8d0e10c80767ylavic

17e6c95f3b22d18acdf8380fb26a8d0e10c80767ylavic <refnamediv>

17e6c95f3b22d18acdf8380fb26a8d0e10c80767ylavic <refname>lwres_gethostbyname</refname>

17e6c95f3b22d18acdf8380fb26a8d0e10c80767ylavic <refname>lwres_gethostbyname2</refname>

e8bd80a4bb88199d2f9a24a50345688e52d9c116ylavic <refname>lwres_gethostbyaddr</refname>

e8bd80a4bb88199d2f9a24a50345688e52d9c116ylavic <refname>lwres_gethostent</refname>

e8bd80a4bb88199d2f9a24a50345688e52d9c116ylavic <refname>lwres_sethostent</refname>

330e16bea8fe9cace4de90c349750c03dfb1fe64ylavic <refname>lwres_endhostent</refname>

330e16bea8fe9cace4de90c349750c03dfb1fe64ylavic <refname>lwres_gethostbyname_r</refname>

330e16bea8fe9cace4de90c349750c03dfb1fe64ylavic <refname>lwres_gethostbyaddr_r</refname>

330e16bea8fe9cace4de90c349750c03dfb1fe64ylavic <refname>lwres_gethostent_r</refname>

330e16bea8fe9cace4de90c349750c03dfb1fe64ylavic <refname>lwres_sethostent_r</refname>

330e16bea8fe9cace4de90c349750c03dfb1fe64ylavic <refname>lwres_endhostent_r</refname>

330e16bea8fe9cace4de90c349750c03dfb1fe64ylavic <refpurpose>lightweight resolver get network host entry</refpurpose>

d7205b1a86c51c27b71a2c458dc453fd53a261c1covener </refnamediv>

d7205b1a86c51c27b71a2c458dc453fd53a261c1covener <refsynopsisdiv>

d7205b1a86c51c27b71a2c458dc453fd53a261c1covener <funcsynopsis>

d7205b1a86c51c27b71a2c458dc453fd53a261c1covener<funcsynopsisinfo>#include &lt;lwres/netdb.h&gt;</funcsynopsisinfo>

d7205b1a86c51c27b71a2c458dc453fd53a261c1covener<funcprototype>

44ff304057225e944e220e981d434a046d14cf06covener <funcdef>

44ff304057225e944e220e981d434a046d14cf06covenerstruct hostent *

44ff304057225e944e220e981d434a046d14cf06covener<function>lwres_gethostbyname</function></funcdef>

44ff304057225e944e220e981d434a046d14cf06covener <paramdef>const char *<parameter>name</parameter></paramdef>

5d1ba75b8794925e67591c209085a49279791de9covener </funcprototype>

5d1ba75b8794925e67591c209085a49279791de9covener<funcprototype>

5d1ba75b8794925e67591c209085a49279791de9covener <funcdef>

032982212dbcc7c3cce95bf89c503bb56e185ac7kbrandstruct hostent *

032982212dbcc7c3cce95bf89c503bb56e185ac7kbrand<function>lwres_gethostbyname2</function></funcdef>

032982212dbcc7c3cce95bf89c503bb56e185ac7kbrand <paramdef>const char *<parameter>name</parameter></paramdef>

032982212dbcc7c3cce95bf89c503bb56e185ac7kbrand <paramdef>int <parameter>af</parameter></paramdef>

caad2986f81ab263f7af41467dd622dc9add17f3ylavic </funcprototype>

caad2986f81ab263f7af41467dd622dc9add17f3ylavic<funcprototype>

caad2986f81ab263f7af41467dd622dc9add17f3ylavic <funcdef>

caad2986f81ab263f7af41467dd622dc9add17f3ylavicstruct hostent *

45a10d38e6051fd7bdf9d742aaae633d97ff02abjailletc<function>lwres_gethostbyaddr</function></funcdef>

f7317ff316c2b141feea31bddb74d5d3fa1584edjorton <paramdef>const char *<parameter>addr</parameter></paramdef>

f7317ff316c2b141feea31bddb74d5d3fa1584edjorton <paramdef>int <parameter>len</parameter></paramdef>

2165214331e4afafca4048f66f303d0253d7b001covener <paramdef>int <parameter>type</parameter></paramdef>

a34684a59b60a4173c25035d0c627ef17e6dc215rpluem </funcprototype>

a34684a59b60a4173c25035d0c627ef17e6dc215rpluem<funcprototype>

1e2d421a36999d292042a5539971070d54aa6c63ylavic <funcdef>

1e2d421a36999d292042a5539971070d54aa6c63ylavicstruct hostent *

1e2d421a36999d292042a5539971070d54aa6c63ylavic<function>lwres_gethostent</function></funcdef>

fa7ed98b9dc94c5845cf845aea0a44ecacd290c9humbedooh <paramdef>void</paramdef>

fa7ed98b9dc94c5845cf845aea0a44ecacd290c9humbedooh </funcprototype>

fa7ed98b9dc94c5845cf845aea0a44ecacd290c9humbedooh<funcprototype>

0b67eb8568cd58bb77082703951679b42cf098actrawick <funcdef>

0b67eb8568cd58bb77082703951679b42cf098actrawickvoid

0b67eb8568cd58bb77082703951679b42cf098actrawick<function>lwres_sethostent</function></funcdef>

0b67eb8568cd58bb77082703951679b42cf098actrawick <paramdef>int <parameter>stayopen</parameter></paramdef>

5ef3c61605a3a021ff71f488983cb0065f8e1a79covener </funcprototype>

fb1985a97912b25ec6564c73e610a31e5fc6e25fcovener<funcprototype>

09c87c777bed1655621bb20e1c46cb6b1a63279dcovener <funcdef>

6502b7b32f980cc2093bb3ebce37e5e4dc68fba4ylavicvoid

6502b7b32f980cc2093bb3ebce37e5e4dc68fba4ylavic<function>lwres_endhostent</function></funcdef>

3060ce7f798fbda7999cd4ddf89b525d2b294185covener <paramdef>void</paramdef>

c1a63b8fad09c419c1a64f75993feb8a343a6801ylavic </funcprototype>

c1a63b8fad09c419c1a64f75993feb8a343a6801ylavic<funcprototype>

c1a63b8fad09c419c1a64f75993feb8a343a6801ylavic <funcdef>

e6b4bd1113567627ab6bb6c6a7105e1e01a7d889jailletcstruct hostent *

e6b4bd1113567627ab6bb6c6a7105e1e01a7d889jailletc<function>lwres_gethostbyname_r</function></funcdef>

e466c40e1801982602ee0200c9e8b61cc148742djailletc <paramdef>const char *<parameter>name</parameter></paramdef>

e466c40e1801982602ee0200c9e8b61cc148742djailletc <paramdef>struct hostent *<parameter>resbuf</parameter></paramdef>

457468b82e59d01eba00dd9d0817309c8f5e414ejim <paramdef>char *<parameter>buf</parameter></paramdef>

457468b82e59d01eba00dd9d0817309c8f5e414ejim <paramdef>int <parameter>buflen</parameter></paramdef>

457468b82e59d01eba00dd9d0817309c8f5e414ejim <paramdef>int *<parameter>error</parameter></paramdef>

04983e3bd1754764eec7d6bb772fe3b0bf391771jorton </funcprototype>

04983e3bd1754764eec7d6bb772fe3b0bf391771jorton<funcprototype>

15890c9306ba98f6fc243e15a3c4778ddc7d773erpluem <funcdef>

15660979a30d251681463de2e0584853890082accovenerstruct hostent *

15660979a30d251681463de2e0584853890082accovener<function>lwres_gethostbyaddr_r</function></funcdef>

49dacedb6c387b786b7911082ff35121a45f414bcovener <paramdef>const char *<parameter>addr</parameter></paramdef>

49dacedb6c387b786b7911082ff35121a45f414bcovener <paramdef>int <parameter>len</parameter></paramdef>

cfd9415521847b2f9394fad04fb701cfb955f503rjung <paramdef>int <parameter>type</parameter></paramdef>

cfd9415521847b2f9394fad04fb701cfb955f503rjung <paramdef>struct hostent *<parameter>resbuf</parameter></paramdef>

cfd9415521847b2f9394fad04fb701cfb955f503rjung <paramdef>char *<parameter>buf</parameter></paramdef>

28c31fb73c1264bd1d0ff932573677030b024c7dwrowe <paramdef>int <parameter>buflen</parameter></paramdef>

28c31fb73c1264bd1d0ff932573677030b024c7dwrowe <paramdef>int *<parameter>error</parameter></paramdef>

28c31fb73c1264bd1d0ff932573677030b024c7dwrowe </funcprototype>

28c31fb73c1264bd1d0ff932573677030b024c7dwrowe<funcprototype>

28c31fb73c1264bd1d0ff932573677030b024c7dwrowe <funcdef>

8491e0600f69b0405e156ea8a419653c065c645bcovenerstruct hostent *

63b9f1f5880391261705f696d7d65507bbe9ace3covener<function>lwres_gethostent_r</function></funcdef>

63b9f1f5880391261705f696d7d65507bbe9ace3covener <paramdef>struct hostent *<parameter>resbuf</parameter></paramdef>

63b9f1f5880391261705f696d7d65507bbe9ace3covener <paramdef>char *<parameter>buf</parameter></paramdef>

49dacedb6c387b786b7911082ff35121a45f414bcovener <paramdef>int <parameter>buflen</parameter></paramdef>

49dacedb6c387b786b7911082ff35121a45f414bcovener <paramdef>int *<parameter>error</parameter></paramdef>

49dacedb6c387b786b7911082ff35121a45f414bcovener </funcprototype>

49dacedb6c387b786b7911082ff35121a45f414bcovener<funcprototype>

3c990331fc6702119e4f5b8ba9eae3021aea5265jim <funcdef>

3c990331fc6702119e4f5b8ba9eae3021aea5265jimvoid

3c990331fc6702119e4f5b8ba9eae3021aea5265jim<function>lwres_sethostent_r</function></funcdef>

3c990331fc6702119e4f5b8ba9eae3021aea5265jim <paramdef>int <parameter>stayopen</parameter></paramdef>

fc42512879dd0504532f52fe5d0d0383dda96a1eniq </funcprototype>

fc42512879dd0504532f52fe5d0d0383dda96a1eniq<funcprototype>

fc42512879dd0504532f52fe5d0d0383dda96a1eniq <funcdef>

0451df5dc50fa5d8b3e07d92ee6a92e36a1181a5niqvoid

0451df5dc50fa5d8b3e07d92ee6a92e36a1181a5niq<function>lwres_endhostent_r</function></funcdef>

0451df5dc50fa5d8b3e07d92ee6a92e36a1181a5niq <paramdef>void</paramdef>

da0442c0440caef34706e2c2f3af05cb65921cc0jailletc </funcprototype>

983528026996668ea295be95aedb9c7a346af470ylavic</funcsynopsis>

da0442c0440caef34706e2c2f3af05cb65921cc0jailletc </refsynopsisdiv>

da0442c0440caef34706e2c2f3af05cb65921cc0jailletc

06b8f183140c8e02e0974e938a05078b511d1603covener <refsect1>

06b8f183140c8e02e0974e938a05078b511d1603covener <title>DESCRIPTION</title>

06b8f183140c8e02e0974e938a05078b511d1603covener <para>

15890c9306ba98f6fc243e15a3c4778ddc7d773erpluem These functions provide hostname-to-address and

259878293a997ff49f5ddfc53d3739cbdc25444ecovener address-to-hostname lookups by means of the lightweight resolver.

259878293a997ff49f5ddfc53d3739cbdc25444ecovener They are similar to the standard

259878293a997ff49f5ddfc53d3739cbdc25444ecovener <citerefentry>

259878293a997ff49f5ddfc53d3739cbdc25444ecovener <refentrytitle>gethostent</refentrytitle><manvolnum>3</manvolnum>

15890c9306ba98f6fc243e15a3c4778ddc7d773erpluem </citerefentry>

b54b024c06a19926832d77d40ba35ad8c41e4d3dminfrin functions provided by most operating systems.

b54b024c06a19926832d77d40ba35ad8c41e4d3dminfrin They use a

b54b024c06a19926832d77d40ba35ad8c41e4d3dminfrin <type>struct hostent</type>

65967d05f839dbf27cf91d91fa79585eeae19660minfrin which is usually defined in

65967d05f839dbf27cf91d91fa79585eeae19660minfrin <filename>&lt;namedb.h&gt;</filename>.

65967d05f839dbf27cf91d91fa79585eeae19660minfrin </para>

65967d05f839dbf27cf91d91fa79585eeae19660minfrin <para><programlisting>

8152945ae46857b170cb227e79bb799f4fc7710dminfrinstruct hostent {

8152945ae46857b170cb227e79bb799f4fc7710dminfrin char *h_name; /* official name of host */

8152945ae46857b170cb227e79bb799f4fc7710dminfrin char **h_aliases; /* alias list */

8152945ae46857b170cb227e79bb799f4fc7710dminfrin int h_addrtype; /* host address type */

75f5c2db254c0167a0e396254460de09b775d203trawick int h_length; /* length of address */

75f5c2db254c0167a0e396254460de09b775d203trawick char **h_addr_list; /* list of addresses from name server */

75f5c2db254c0167a0e396254460de09b775d203trawick};

4f0358189bfa57b8e75bd6b94db264302a8f336amrumph#define h_addr h_addr_list[0] /* address, for backward compatibility */

4f0358189bfa57b8e75bd6b94db264302a8f336amrumph</programlisting>

4f0358189bfa57b8e75bd6b94db264302a8f336amrumph </para>

5716f9c6daa92dde5f2f9d11ed63f7c9549c223atrawick <para>

5716f9c6daa92dde5f2f9d11ed63f7c9549c223atrawick The members of this structure are:

5716f9c6daa92dde5f2f9d11ed63f7c9549c223atrawick <variablelist>

5716f9c6daa92dde5f2f9d11ed63f7c9549c223atrawick <varlistentry>

54d750a84a175d8e338880514d440773eb986b50covener <term><constant>h_name</constant></term>

54d750a84a175d8e338880514d440773eb986b50covener <listitem>

54d750a84a175d8e338880514d440773eb986b50covener <para>

54d750a84a175d8e338880514d440773eb986b50covener The official (canonical) name of the host.

54d750a84a175d8e338880514d440773eb986b50covener </para>

54d750a84a175d8e338880514d440773eb986b50covener </listitem>

54d750a84a175d8e338880514d440773eb986b50covener </varlistentry>

54d750a84a175d8e338880514d440773eb986b50covener <varlistentry>

7a3aa12f0eda24793ee26d6a179bd53132e9dae8covener <term><constant>h_aliases</constant></term>

54d750a84a175d8e338880514d440773eb986b50covener <listitem>

54d750a84a175d8e338880514d440773eb986b50covener <para>

83b50288fa7d306324bba68832011ea08f5c7832covener A NULL-terminated array of alternate names (nicknames) for the

4e30ef014533a7e93c92d88306291f5e49c9692ftrawick host.

83b50288fa7d306324bba68832011ea08f5c7832covener </para>

5f066f496cd9f20a2a701255bc67d44e7cb46daetrawick </listitem>

5f066f496cd9f20a2a701255bc67d44e7cb46daetrawick </varlistentry>

5f066f496cd9f20a2a701255bc67d44e7cb46daetrawick <varlistentry>

2e15620d724fb8e3a5be183b917359a2fd6e9468covener <term><constant>h_addrtype</constant></term>

2e15620d724fb8e3a5be183b917359a2fd6e9468covener <listitem>

2e15620d724fb8e3a5be183b917359a2fd6e9468covener <para>

2e15620d724fb8e3a5be183b917359a2fd6e9468covener The type of address being returned &mdash;

1b988c41ee505962781d110a3e4c2c90f1ea0aa4covener <type>PF_INET</type>

1b988c41ee505962781d110a3e4c2c90f1ea0aa4covener or

1b988c41ee505962781d110a3e4c2c90f1ea0aa4covener <type>PF_INET6</type>.

1b988c41ee505962781d110a3e4c2c90f1ea0aa4covener </para>

b8efdc95bec9cf089aa1be0bfd07d46aa1137a7acovener </listitem>

b8efdc95bec9cf089aa1be0bfd07d46aa1137a7acovener </varlistentry>

b8efdc95bec9cf089aa1be0bfd07d46aa1137a7acovener <varlistentry>

f06e7c4b1bce6b6491e5de0b7998d3f5696b293dchrisd <term><constant>h_length</constant></term>

f06e7c4b1bce6b6491e5de0b7998d3f5696b293dchrisd <listitem>

f06e7c4b1bce6b6491e5de0b7998d3f5696b293dchrisd <para>

179565be4043d7e5f9161aa75271fa0a001866d9covener The length of the address in bytes.

179565be4043d7e5f9161aa75271fa0a001866d9covener </para>

179565be4043d7e5f9161aa75271fa0a001866d9covener </listitem>

111436a32ba1254291e4883292fb116d15fe8f64covener </varlistentry>

fce4949fb0b309a5744afcd503c6ed2d35621ee2covener <varlistentry>

fce4949fb0b309a5744afcd503c6ed2d35621ee2covener <term><constant>h_addr_list</constant></term>

fce4949fb0b309a5744afcd503c6ed2d35621ee2covener <listitem>

fce4949fb0b309a5744afcd503c6ed2d35621ee2covener <para>

7b7430e701e9a31ce809da7c220bb8dfcf68c86etrawick A <type>NULL</type>

7b7430e701e9a31ce809da7c220bb8dfcf68c86etrawick terminated array of network addresses for the host.

7b7430e701e9a31ce809da7c220bb8dfcf68c86etrawick Host addresses are returned in network byte order.

ccc20788c1e5fc973f36df634399c89acb70deaejerenkrantz </para>

ccc20788c1e5fc973f36df634399c89acb70deaejerenkrantz </listitem>

ccc20788c1e5fc973f36df634399c89acb70deaejerenkrantz </varlistentry>

273e512f20f262e5e2aa8e0e83371d1929fb76adjkaluza </variablelist>

273e512f20f262e5e2aa8e0e83371d1929fb76adjkaluza </para>

273e512f20f262e5e2aa8e0e83371d1929fb76adjkaluza <para>

efe780dcf13b2b95effabf897d694d8f23feac74trawick For backward compatibility with very old software,

fe83f60b41477b14a37edcfcd1f7f5c5a1ebfe44minfrin <constant>h_addr</constant>

fe83f60b41477b14a37edcfcd1f7f5c5a1ebfe44minfrin is the first address in

fe83f60b41477b14a37edcfcd1f7f5c5a1ebfe44minfrin <constant>h_addr_list.</constant>

993d1261a278d7322bccef219101220b7b4fb8c5jkaluza </para>

993d1261a278d7322bccef219101220b7b4fb8c5jkaluza <para><function>lwres_gethostent()</function>,

993d1261a278d7322bccef219101220b7b4fb8c5jkaluza <function>lwres_sethostent()</function>,

ba050a6f942b9fa0e81ed73437588005c569655ccovener <function>lwres_endhostent()</function>,

ba050a6f942b9fa0e81ed73437588005c569655ccovener <function>lwres_gethostent_r()</function>,

ba050a6f942b9fa0e81ed73437588005c569655ccovener <function>lwres_sethostent_r()</function>

ba050a6f942b9fa0e81ed73437588005c569655ccovener and

135ddda3a989215d2bedbcf1529bfb269c3eda23niq <function>lwres_endhostent_r()</function>

135ddda3a989215d2bedbcf1529bfb269c3eda23niq provide iteration over the known host entries on systems that

135ddda3a989215d2bedbcf1529bfb269c3eda23niq provide such functionality through facilities like

001a44c352f89c9ec332ffd3e0a6927dcd19432chumbedooh <filename>/etc/hosts</filename>

001a44c352f89c9ec332ffd3e0a6927dcd19432chumbedooh or NIS. The lightweight resolver does not currently implement

001a44c352f89c9ec332ffd3e0a6927dcd19432chumbedooh these functions; it only provides them as stub functions that always

efe780dcf13b2b95effabf897d694d8f23feac74trawick return failure.

793214f67dede32edfd9ee96c664ead04d175cbbjfclere </para>

cc5a4a08dc9783fcbc52ce86f11e01c281a43810minfrin

9b0076ddd1103e5fa9c1f9bafde4b06ce244fbaecovener <para><function>lwres_gethostbyname()</function>

9b0076ddd1103e5fa9c1f9bafde4b06ce244fbaecovener and <function>lwres_gethostbyname2()</function> look up the

9b0076ddd1103e5fa9c1f9bafde4b06ce244fbaecovener hostname <parameter>name</parameter>.

249d09d51808cb7981af99762c3b3736ca126cd5jkaluza <function>lwres_gethostbyname()</function> always looks for an

249d09d51808cb7981af99762c3b3736ca126cd5jkaluza IPv4 address while <function>lwres_gethostbyname2()</function>

249d09d51808cb7981af99762c3b3736ca126cd5jkaluza looks for an address of protocol family

249d09d51808cb7981af99762c3b3736ca126cd5jkaluza <parameter>af</parameter>: either <type>PF_INET</type> or

56589be3d7a3e9343370df240010c6928cc78b39jkaluza <type>PF_INET6</type> &mdash; IPv4 or IPV6 addresses

56589be3d7a3e9343370df240010c6928cc78b39jkaluza respectively. Successful calls of the functions return a

56589be3d7a3e9343370df240010c6928cc78b39jkaluza <type>struct hostent</type>for the name that was looked up.

77ca16c5676da23155311e13cee61e7eaba9fa3ejailletc <type>NULL</type> is returned if the lookups by

77ca16c5676da23155311e13cee61e7eaba9fa3ejailletc <function>lwres_gethostbyname()</function> or

77ca16c5676da23155311e13cee61e7eaba9fa3ejailletc <function>lwres_gethostbyname2()</function> fail.

77ca16c5676da23155311e13cee61e7eaba9fa3ejailletc </para>

f87299dab99bc04b51a6b8cad51b6795db862c0atrawick

f87299dab99bc04b51a6b8cad51b6795db862c0atrawick <para>

f87299dab99bc04b51a6b8cad51b6795db862c0atrawick Reverse lookups of addresses are performed by

4d12805e6c18253040223ea637acd6b3b3c18f60jorton <function>lwres_gethostbyaddr()</function>.

4d12805e6c18253040223ea637acd6b3b3c18f60jorton <parameter>addr</parameter> is an address of length

4d12805e6c18253040223ea637acd6b3b3c18f60jorton <parameter>len</parameter> bytes and protocol family

85eacfc96a04547ef25aabbc06440039715084c2jorton <parameter>type</parameter> &mdash; <type>PF_INET</type> or

85eacfc96a04547ef25aabbc06440039715084c2jorton <type>PF_INET6</type>.

e5d909f2b06bd880fb3675cd49363df981caa631trawick <function>lwres_gethostbyname_r()</function> is a

a4df2cd1e1391575a327c2a90ba4315f805a0a78covener thread-safe function

a4df2cd1e1391575a327c2a90ba4315f805a0a78covener for forward lookups. If an error occurs, an error code is returned in

a4df2cd1e1391575a327c2a90ba4315f805a0a78covener <parameter>*error</parameter>.

cb666b29f81df1d11d65002250153353568021fccovener <parameter>resbuf</parameter> is a pointer to a

cb666b29f81df1d11d65002250153353568021fccovener <type>struct hostent</type> which is initialised by a successful call to

cb666b29f81df1d11d65002250153353568021fccovener <function>lwres_gethostbyname_r()</function>.

6a80c3c6f4b8ea7ba5e89402b8b779b09ce020e0covener <parameter>buf</parameter> is a buffer of length

1c2cab00d988fc48cbe59032cf76cc0bab20d6f7covener <parameter>len</parameter> bytes which is used to store the

6a80c3c6f4b8ea7ba5e89402b8b779b09ce020e0covener <constant>h_name</constant>, <constant>h_aliases</constant>, and

75a230a728338d84dcfe81edd375352f34de22d0covener <constant>h_addr_list</constant> elements of the

75a230a728338d84dcfe81edd375352f34de22d0covener <type>struct hostent</type> returned in <parameter>resbuf</parameter>.

75a230a728338d84dcfe81edd375352f34de22d0covener Successful calls to <function>lwres_gethostbyname_r()</function>

1f50dc34ae069adeed20b2986e5ffdefa5c410e0covener return <parameter>resbuf</parameter>,

1f50dc34ae069adeed20b2986e5ffdefa5c410e0covener which is a pointer to the <type>struct hostent</type> it created.

1f50dc34ae069adeed20b2986e5ffdefa5c410e0covener </para>

63a5ea80bddcc84a462e40f402b4f330e0e05411covener

63a5ea80bddcc84a462e40f402b4f330e0e05411covener <para><function>lwres_gethostbyaddr_r()</function>

63a5ea80bddcc84a462e40f402b4f330e0e05411covener is a thread-safe function

63a5ea80bddcc84a462e40f402b4f330e0e05411covener that performs a reverse lookup of address <parameter>addr</parameter>

65a4e663b82f8bce28ac22ab2edfd7502de36998sf which is <parameter>len</parameter> bytes long and is of

65a4e663b82f8bce28ac22ab2edfd7502de36998sf protocol

65a4e663b82f8bce28ac22ab2edfd7502de36998sf family <parameter>type</parameter> &mdash; <type>PF_INET</type> or

65a4e663b82f8bce28ac22ab2edfd7502de36998sf <type>PF_INET6</type>. If an error occurs, the error code is returned

c7de1955eb0eaeabf7042902476397692672d549sf in <parameter>*error</parameter>. The other function

74e7f6c55fd67b10cb400b3f6d1dc718a303d944minfrin parameters are

74e7f6c55fd67b10cb400b3f6d1dc718a303d944minfrin identical to those in <function>lwres_gethostbyname_r()</function>.

74e7f6c55fd67b10cb400b3f6d1dc718a303d944minfrin <parameter>resbuf</parameter> is a pointer to a

74e7f6c55fd67b10cb400b3f6d1dc718a303d944minfrin <type>struct hostent</type> which is initialised by a successful call to

a511a29faf2ff7ead3b67680154a624effb31aafminfrin <function>lwres_gethostbyaddr_r()</function>.

a511a29faf2ff7ead3b67680154a624effb31aafminfrin <parameter>buf</parameter> is a buffer of length

a511a29faf2ff7ead3b67680154a624effb31aafminfrin <parameter>len</parameter> bytes which is used to store the

a511a29faf2ff7ead3b67680154a624effb31aafminfrin <constant>h_name</constant>, <constant>h_aliases</constant>, and

a511a29faf2ff7ead3b67680154a624effb31aafminfrin <constant>h_addr_list</constant> elements of the

63921358ef93fcb41bc71d9894221ba3d7fbb87bminfrin <type>struct hostent</type> returned in <parameter>resbuf</parameter>.

63921358ef93fcb41bc71d9894221ba3d7fbb87bminfrin Successful calls to <function>lwres_gethostbyaddr_r()</function> return

63921358ef93fcb41bc71d9894221ba3d7fbb87bminfrin <parameter>resbuf</parameter>, which is a pointer to the

deec48c67d4786bc77112ffbf3a4e70b931097edminfrin <function>struct hostent()</function> it created.

6d601599d3d65df0410eae6e573e75b2dbfb1fb4minfrin </para>

6d601599d3d65df0410eae6e573e75b2dbfb1fb4minfrin

6d601599d3d65df0410eae6e573e75b2dbfb1fb4minfrin </refsect1>

6d601599d3d65df0410eae6e573e75b2dbfb1fb4minfrin

684e0cfc200f66287a93bbd1708d1dd8a92a7eefcovener <refsect1>

684e0cfc200f66287a93bbd1708d1dd8a92a7eefcovener <title>RETURN VALUES</title>

5c43d2fb853f84497b5ece2d414ef9484aa87e5fsf <para>

05a5a9c3e16f21566e1b61f4bd68025ce1b741ccjoes The functions

05a5a9c3e16f21566e1b61f4bd68025ce1b741ccjoes <function>lwres_gethostbyname()</function>,

ef82e8fa164e0a1f8b813f7deb6b7ead96018c94niq <function>lwres_gethostbyname2()</function>,

26c5829347f6a355c00f1ba0301d575056b69536niq <function>lwres_gethostbyaddr()</function>,

ef82e8fa164e0a1f8b813f7deb6b7ead96018c94niq and

ef82e8fa164e0a1f8b813f7deb6b7ead96018c94niq <function>lwres_gethostent()</function>

ef82e8fa164e0a1f8b813f7deb6b7ead96018c94niq return NULL to indicate an error. In this case the global variable

ef82e8fa164e0a1f8b813f7deb6b7ead96018c94niq <type>lwres_h_errno</type>

ef82e8fa164e0a1f8b813f7deb6b7ead96018c94niq will contain one of the following error codes defined in

ef82e8fa164e0a1f8b813f7deb6b7ead96018c94niq <filename>&lt;lwres/netdb.h&gt;</filename>:

413ee814748f37be168ff12407fa6dba0ceeabe6trawick

c12917da693bae4028a1d5a5e8224bceed8c739dsf <variablelist>

c12917da693bae4028a1d5a5e8224bceed8c739dsf <varlistentry>

eafcc0ebf263d0ba69855b6e10958c4c1a2361bdsf <term><constant>HOST_NOT_FOUND</constant></term>

eafcc0ebf263d0ba69855b6e10958c4c1a2361bdsf <listitem>

eafcc0ebf263d0ba69855b6e10958c4c1a2361bdsf <para>

eafcc0ebf263d0ba69855b6e10958c4c1a2361bdsf The host or address was not found.

eafcc0ebf263d0ba69855b6e10958c4c1a2361bdsf </para>

d7ffd2da16d58b1a0de212e4d56f7aebb72bef26sf </listitem>

d7ffd2da16d58b1a0de212e4d56f7aebb72bef26sf </varlistentry>

d7ffd2da16d58b1a0de212e4d56f7aebb72bef26sf <varlistentry>

4576c1a9ef54cd1e5555ee07d016a7f559f80338sf <term><constant>TRY_AGAIN</constant></term>

4576c1a9ef54cd1e5555ee07d016a7f559f80338sf <listitem>

4576c1a9ef54cd1e5555ee07d016a7f559f80338sf <para>

9811aed12bbc71783d2e544ccb5fecd193843eadsf A recoverable error occurred, e.g., a timeout.

9811aed12bbc71783d2e544ccb5fecd193843eadsf Retrying the lookup may succeed.

9811aed12bbc71783d2e544ccb5fecd193843eadsf </para>

88fac54d9d64f85bbdab5d7010816f4377f95bd7rjung </listitem>

88fac54d9d64f85bbdab5d7010816f4377f95bd7rjung </varlistentry>

bd3f5647b96d378d9c75c954e3f13582af32c643sf <varlistentry>

bd3f5647b96d378d9c75c954e3f13582af32c643sf <term><constant>NO_RECOVERY</constant></term>

bd3f5647b96d378d9c75c954e3f13582af32c643sf <listitem>

bd3f5647b96d378d9c75c954e3f13582af32c643sf <para>

bd3f5647b96d378d9c75c954e3f13582af32c643sf A non-recoverable error occurred.

2a7beea91d46beb41f043a84eaad060047ee04aafabien </para>

2a7beea91d46beb41f043a84eaad060047ee04aafabien </listitem>

2a7beea91d46beb41f043a84eaad060047ee04aafabien </varlistentry>

2a7beea91d46beb41f043a84eaad060047ee04aafabien <varlistentry>

584a85dd4047e38d3ed3a29b6662fcc9d100ae4csf <term><constant>NO_DATA</constant></term>

584a85dd4047e38d3ed3a29b6662fcc9d100ae4csf <listitem>

584a85dd4047e38d3ed3a29b6662fcc9d100ae4csf <para>

f21e9e3d0bfb7a507ecc5bc963f2159d693503d1sf The name exists, but has no address information

f21e9e3d0bfb7a507ecc5bc963f2159d693503d1sf associated with it (or vice versa in the case

f21e9e3d0bfb7a507ecc5bc963f2159d693503d1sf of a reverse lookup). The code NO_ADDRESS

f6b9c755a0b793e8a3a3aebd327ca20a86478117sf is accepted as a synonym for NO_DATA for backwards

f6b9c755a0b793e8a3a3aebd327ca20a86478117sf compatibility.

f6b9c755a0b793e8a3a3aebd327ca20a86478117sf </para>

132ee6ac1c26d6e8953836316ba50734eefab47bsf </listitem>

132ee6ac1c26d6e8953836316ba50734eefab47bsf </varlistentry>

132ee6ac1c26d6e8953836316ba50734eefab47bsf </variablelist>

85eacfc96a04547ef25aabbc06440039715084c2jorton </para>

85eacfc96a04547ef25aabbc06440039715084c2jorton

85eacfc96a04547ef25aabbc06440039715084c2jorton <para><citerefentry>

536d2e7cd1fdec1255b8c3bdf41fdc714c506a54trawick <refentrytitle>lwres_hstrerror</refentrytitle><manvolnum>3</manvolnum>

536d2e7cd1fdec1255b8c3bdf41fdc714c506a54trawick </citerefentry>

536d2e7cd1fdec1255b8c3bdf41fdc714c506a54trawick translates these error codes to suitable error messages.

536d2e7cd1fdec1255b8c3bdf41fdc714c506a54trawick </para>

79c5787b92ac5f0e1cc82393816c77a006399316trawick

79c5787b92ac5f0e1cc82393816c77a006399316trawick <para><function>lwres_gethostent()</function>

79c5787b92ac5f0e1cc82393816c77a006399316trawick and <function>lwres_gethostent_r()</function>

79c5787b92ac5f0e1cc82393816c77a006399316trawick always return <type>NULL</type>.

c967bf3bc89e8aa60dbd30d9da388e448ddc1cc4trawick </para>

79c5787b92ac5f0e1cc82393816c77a006399316trawick

79c5787b92ac5f0e1cc82393816c77a006399316trawick <para>

79c5787b92ac5f0e1cc82393816c77a006399316trawick Successful calls to <function>lwres_gethostbyname_r()</function> and

79c5787b92ac5f0e1cc82393816c77a006399316trawick <function>lwres_gethostbyaddr_r()</function> return

79c5787b92ac5f0e1cc82393816c77a006399316trawick <parameter>resbuf</parameter>, a pointer to the

7b395e4e878c28a4784919cfd2e704ddd14a3390jorton <type>struct hostent</type> that was initialised by these functions. They return

7b395e4e878c28a4784919cfd2e704ddd14a3390jorton <type>NULL</type> if the lookups fail or if <parameter>buf</parameter>

7b395e4e878c28a4784919cfd2e704ddd14a3390jorton was too small to hold the list of addresses and names referenced by

7b395e4e878c28a4784919cfd2e704ddd14a3390jorton the <constant>h_name</constant>, <constant>h_aliases</constant>, and

536e48c08d674acac5d44929318f2ad928edc361jorton <constant>h_addr_list</constant> elements of the

536e48c08d674acac5d44929318f2ad928edc361jorton <type>struct hostent</type>.

e81785da447b469da66f218b3f0244aab507958djorton If <parameter>buf</parameter> was too small, both

e81785da447b469da66f218b3f0244aab507958djorton <function>lwres_gethostbyname_r()</function> and

3e4e54d4e3fc0123c63d57aa84ac7ad7a8c73ff8jorton <function>lwres_gethostbyaddr_r()</function> set the global

3e4e54d4e3fc0123c63d57aa84ac7ad7a8c73ff8jorton variable

3e4e54d4e3fc0123c63d57aa84ac7ad7a8c73ff8jorton <type>errno</type> to <errorcode>ERANGE</errorcode>.

53e9b27aba029b18be814df40bcf6f0428771d1efuankg </para>

53e9b27aba029b18be814df40bcf6f0428771d1efuankg

53e9b27aba029b18be814df40bcf6f0428771d1efuankg </refsect1>

53e9b27aba029b18be814df40bcf6f0428771d1efuankg <refsect1>

53e9b27aba029b18be814df40bcf6f0428771d1efuankg <title>SEE ALSO</title>

6bb524f1895f30265a1431afc460977d391cb36bsf <para><citerefentry>

6bb524f1895f30265a1431afc460977d391cb36bsf <refentrytitle>gethostent</refentrytitle><manvolnum>3</manvolnum>

ca61ccd0c306c2c72df153688ba1b49f3eceed80sf </citerefentry>,

6bb524f1895f30265a1431afc460977d391cb36bsf

e6dd71992459d05a676b98b7963423dc5dc1e24aminfrin <citerefentry>

e6dd71992459d05a676b98b7963423dc5dc1e24aminfrin <refentrytitle>lwres_getipnode</refentrytitle><manvolnum>3</manvolnum>

e6dd71992459d05a676b98b7963423dc5dc1e24aminfrin </citerefentry>,

e6dd71992459d05a676b98b7963423dc5dc1e24aminfrin

23f1535d6a60817d2846bac0aea230ea475d7dccminfrin <citerefentry>

23f1535d6a60817d2846bac0aea230ea475d7dccminfrin <refentrytitle>lwres_hstrerror</refentrytitle><manvolnum>3</manvolnum>

23f1535d6a60817d2846bac0aea230ea475d7dccminfrin </citerefentry>

23f1535d6a60817d2846bac0aea230ea475d7dccminfrin </para>

ec7520b24cd80d34d82bbcaca153cbb23cc04bc0rjung </refsect1>

ec7520b24cd80d34d82bbcaca153cbb23cc04bc0rjung

ec7520b24cd80d34d82bbcaca153cbb23cc04bc0rjung <refsect1>

ec7520b24cd80d34d82bbcaca153cbb23cc04bc0rjung <title>BUGS</title>

ec7520b24cd80d34d82bbcaca153cbb23cc04bc0rjung <para><function>lwres_gethostbyname()</function>,

ec7520b24cd80d34d82bbcaca153cbb23cc04bc0rjung <function>lwres_gethostbyname2()</function>,

ec7520b24cd80d34d82bbcaca153cbb23cc04bc0rjung <function>lwres_gethostbyaddr()</function>

ec7520b24cd80d34d82bbcaca153cbb23cc04bc0rjung and

6249dfa569d3b4f1f539665b979a80c6e335d93etrawick <function>lwres_endhostent()</function>

6249dfa569d3b4f1f539665b979a80c6e335d93etrawick are not thread safe; they return pointers to static data and

0827cb14e550f6f65018431c22c2c913631c8f25kbrand provide error codes through a global variable.

6249dfa569d3b4f1f539665b979a80c6e335d93etrawick Thread-safe versions for name and address lookup are provided by

ae600ca541efc686b34f8b1f21bd3d0741d37674covener <function>lwres_gethostbyname_r()</function>,

6249dfa569d3b4f1f539665b979a80c6e335d93etrawick and

cfa64348224b66dd1c9979b809406c4d15b1c137fielding <function>lwres_gethostbyaddr_r()</function>

74499a117b3b2cd9666715a14f90c0e5d1a4ee8ajim respectively.

cfa64348224b66dd1c9979b809406c4d15b1c137fielding </para>

74499a117b3b2cd9666715a14f90c0e5d1a4ee8ajim <para>

cfa64348224b66dd1c9979b809406c4d15b1c137fielding The resolver daemon does not currently support any non-DNS

74499a117b3b2cd9666715a14f90c0e5d1a4ee8ajim name services such as

cfa64348224b66dd1c9979b809406c4d15b1c137fielding <filename>/etc/hosts</filename>

74499a117b3b2cd9666715a14f90c0e5d1a4ee8ajim or

cfa64348224b66dd1c9979b809406c4d15b1c137fielding <type>NIS</type>,

consequently the above functions don't, either.

</para>

</refsect1>

</refentry><!--