contrib/bind9/lib/lwres/man/lwres_getnameinfo.docbook

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  21 <!-- $Id$ -->
  22 <refentry>
  23
  24   <refentryinfo>
  25     <date>Jun 30, 2000</date>
  26   </refentryinfo>
  27
  28   <refmeta>
  29     <refentrytitle>lwres_getnameinfo</refentrytitle>
  30     <manvolnum>3</manvolnum>
  31     <refmiscinfo>BIND9</refmiscinfo>
  32   </refmeta>
  33
  34   <docinfo>
  35     <copyright>
  36       <year>2004</year>
  37       <year>2005</year>
  38       <year>2007</year>
  39       <year>2012</year>
  40       <holder>Internet Systems Consortium, Inc. ("ISC")</holder>
  41     </copyright>
  42     <copyright>
  43       <year>2000</year>
  44       <year>2001</year>
  45       <holder>Internet Software Consortium.</holder>
  46     </copyright>
  47   </docinfo>
  48
  49   <refnamediv>
  50     <refname>lwres_getnameinfo</refname>
  51     <refpurpose>lightweight resolver socket address structure to hostname and
  52       service name
  53     </refpurpose>
  54   </refnamediv>
  55   <refsynopsisdiv>
  56     <funcsynopsis>
  57 <funcsynopsisinfo>#include &lt;lwres/netdb.h&gt;</funcsynopsisinfo>
  58 <funcprototype>
  59         <funcdef>
  60 int
  61 <function>lwres_getnameinfo</function></funcdef>
  62         <paramdef>const struct sockaddr *<parameter>sa</parameter></paramdef>
  63         <paramdef>size_t <parameter>salen</parameter></paramdef>
  64         <paramdef>char *<parameter>host</parameter></paramdef>
  65         <paramdef>size_t <parameter>hostlen</parameter></paramdef>
  66         <paramdef>char *<parameter>serv</parameter></paramdef>
  67         <paramdef>size_t <parameter>servlen</parameter></paramdef>
  68         <paramdef>int <parameter>flags</parameter></paramdef>
  69       </funcprototype>
  70 </funcsynopsis>
  71   </refsynopsisdiv>
  72
  73   <refsect1>
  74     <title>DESCRIPTION</title>
  75
  76     <para>
  77        This function is equivalent to the
  78       <citerefentry>
  79         <refentrytitle>getnameinfo</refentrytitle><manvolnum>3</manvolnum>
  80       </citerefentry> function defined in RFC2133.
  81       <function>lwres_getnameinfo()</function> returns the
  82       hostname for the
  83       <type>struct sockaddr</type> <parameter>sa</parameter> which
  84       is
  85       <parameter>salen</parameter> bytes long.  The hostname is of
  86       length
  87       <parameter>hostlen</parameter> and is returned via
  88       <parameter>*host.</parameter> The maximum length of the
  89       hostname is
  90       1025 bytes: <constant>NI_MAXHOST</constant>.
  91     </para>
  92
  93     <para> The name of the service associated with the port number in
  94       <parameter>sa</parameter> is returned in <parameter>*serv.</parameter>
  95       It is <parameter>servlen</parameter> bytes long.  The
  96       maximum length
  97       of the service name is <constant>NI_MAXSERV</constant> - 32
  98       bytes.
  99     </para>
 100
 101     <para>
 102        The <parameter>flags</parameter> argument sets the
 103       following
 104       bits:
 105       <variablelist>
 106         <varlistentry>
 107           <term><constant>NI_NOFQDN</constant></term>
 108           <listitem>
 109             <para>
 110               A fully qualified domain name is not required for local hosts.
 111               The local part of the fully qualified domain name is returned
 112               instead.
 113             </para>
 114           </listitem>
 115         </varlistentry>
 116         <varlistentry>
 117           <term><constant>NI_NUMERICHOST</constant></term>
 118           <listitem>
 119             <para>
 120               Return the address in numeric form, as if calling inet_ntop(),
 121               instead of a host name.
 122             </para>
 123           </listitem>
 124         </varlistentry>
 125         <varlistentry>
 126           <term><constant>NI_NAMEREQD</constant></term>
 127           <listitem>
 128             <para>
 129               A name is required. If the hostname cannot be found in the DNS
 130               and
 131               this flag is set, a non-zero error code is returned.
 132               If the hostname is not found and the flag is not set, the
 133               address is returned in numeric form.
 134             </para>
 135           </listitem>
 136         </varlistentry>
 137         <varlistentry>
 138           <term><constant>NI_NUMERICSERV</constant></term>
 139           <listitem>
 140             <para>
 141               The service name is returned as a digit string representing the
 142               port number.
 143             </para>
 144           </listitem>
 145         </varlistentry>
 146         <varlistentry>
 147           <term><constant>NI_DGRAM</constant></term>
 148           <listitem>
 149             <para>
 150               Specifies that the service being looked up is a datagram
 151               service,  and causes getservbyport() to be called with a second
 152               argument of "udp" instead of its default of "tcp".  This is
 153               required
 154               for the few ports (512-514) that have different services for UDP
 155               and
 156               TCP.
 157             </para>
 158           </listitem>
 159         </varlistentry>
 160       </variablelist>
 161     </para>
 162   </refsect1>
 163
 164   <refsect1>
 165     <title>RETURN VALUES</title>
 166     <para><function>lwres_getnameinfo()</function>
 167       returns 0 on success or a non-zero error code if an error occurs.
 168     </para>
 169   </refsect1>
 170   <refsect1>
 171     <title>SEE ALSO</title>
 172     <para><citerefentry>
 173         <refentrytitle>RFC2133</refentrytitle>
 174       </citerefentry>,
 175       <citerefentry>
 176         <refentrytitle>getservbyport</refentrytitle><manvolnum>3</manvolnum>
 177       </citerefentry>,
 178       <citerefentry>
 179         <refentrytitle>lwres</refentrytitle><manvolnum>3</manvolnum>
 180       </citerefentry>,
 181       <citerefentry>
 182         <refentrytitle>lwres_getnameinfo</refentrytitle><manvolnum>3</manvolnum>
 183       </citerefentry>,
 184       <citerefentry>
 185         <refentrytitle>lwres_getnamebyaddr</refentrytitle><manvolnum>3</manvolnum>
 186       </citerefentry>.
 187       <citerefentry>
 188         <refentrytitle>lwres_net_ntop</refentrytitle><manvolnum>3</manvolnum>
 189       </citerefentry>.
 190     </para>
 191   </refsect1>
 192   <refsect1>
 193     <title>BUGS</title>
 194     <para>
 195       RFC2133 fails to define what the nonzero return values of
 196       <citerefentry>
 197         <refentrytitle>getnameinfo</refentrytitle><manvolnum>3</manvolnum>
 198       </citerefentry>
 199       are.
 200     </para>
 201   </refsect1>
 202 </refentry><!--
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