lwres_getnameinfo.html revision 52ece689e0265f9a3e518de5b2539e749f6d35ac
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<!--
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - Copyright (C) 2004, 2005 Internet Systems Consortium, Inc. ("ISC")
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - Copyright (C) 2000, 2001 Internet Software Consortium.
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive -
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - Permission to use, copy, modify, and distribute this software for any
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - purpose with or without fee is hereby granted, provided that the above
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - copyright notice and this permission notice appear in all copies.
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive -
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive - PERFORMANCE OF THIS SOFTWARE.
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive-->
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<!-- $Id: lwres_getnameinfo.html,v 1.19 2006/04/23 10:14:12 marka Exp $ -->
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<html>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<head>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<title>lwres_getnameinfo</title>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<meta name="generator" content="DocBook XSL Stylesheets V1.69.1">
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive</head>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en">
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<a name="id2462968"></a><div class="titlepage"></div>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<div class="refnamediv">
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<h2>Name</h2>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<p>lwres_getnameinfo &#8212; lightweight resolver socket address structure to hostname and
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive service name
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive </p>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive</div>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<div class="refsynopsisdiv">
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<h2>Synopsis</h2>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<div class="funcsynopsis">
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<pre class="funcsynopsisinfo">#include &lt;lwres/netdb.h&gt;</pre>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0">
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<tr>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td><code class="funcdef">
7b02e31b0f0bbca080ed78d2ec5a1398a7388202sliveint
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<b class="fsfunc">lwres_getnameinfo</b>(</code></td>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<td>const struct sockaddr *�</td>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<td>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<var class="pdparam">sa</var>, </td>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive</tr>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<tr>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<td>�</td>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<td>size_t �</td>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<td>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<var class="pdparam">salen</var>, </td>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive</tr>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<tr>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<td>�</td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>char *�</td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<var class="pdparam">host</var>, </td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive</tr>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<tr>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>�</td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>size_t �</td>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<var class="pdparam">hostlen</var>, </td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive</tr>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<tr>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>�</td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>char *�</td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<var class="pdparam">serv</var>, </td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive</tr>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<tr>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>�</td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>size_t �</td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<var class="pdparam">servlen</var>, </td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive</tr>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<tr>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>�</td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>int �</td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<var class="pdparam">flags</var><code>)</code>;</td>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive</tr>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive</table>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive</div>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive</div>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<div class="refsect1" lang="en">
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<a name="id2525202"></a><h2>DESCRIPTION</h2>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<p>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive This function is equivalent to the
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive <span class="citerefentry"><span class="refentrytitle">getnameinfo</span>(3)</span> function defined in RFC2133.
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive <code class="function">lwres_getnameinfo()</code> returns the
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive hostname for the
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive <span class="type">struct sockaddr</span> <em class="parameter"><code>sa</code></em> which
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive is
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive <em class="parameter"><code>salen</code></em> bytes long. The hostname is of
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive length
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive <em class="parameter"><code>hostlen</code></em> and is returned via
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive <em class="parameter"><code>*host.</code></em> The maximum length of the
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive hostname is
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive 1025 bytes: <code class="constant">NI_MAXHOST</code>.
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive </p>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<p> The name of the service associated with the port number in
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive <em class="parameter"><code>sa</code></em> is returned in <em class="parameter"><code>*serv.</code></em>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive It is <em class="parameter"><code>servlen</code></em> bytes long. The
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive maximum length
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive of the service name is <code class="constant">NI_MAXSERV</code> - 32
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive bytes.
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive </p>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive<p>
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive The <em class="parameter"><code>flags</code></em> argument sets the
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive following
7b02e31b0f0bbca080ed78d2ec5a1398a7388202slive bits:
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive </p>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<div class="variablelist"><dl>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<dt><span class="term"><code class="constant">NI_NOFQDN</code></span></dt>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<dd><p>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive A fully qualified domain name is not required for local hosts.
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive The local part of the fully qualified domain name is returned
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive instead.
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive </p></dd>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<dt><span class="term"><code class="constant">NI_NUMERICHOST</code></span></dt>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<dd><p>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive Return the address in numeric form, as if calling inet_ntop(),
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive instead of a host name.
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive </p></dd>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<dt><span class="term"><code class="constant">NI_NAMEREQD</code></span></dt>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive<dd><p>
39439c95488c2e66ea8b35c47f75e9ec2508d8fbslive A name is required. If the hostname cannot be found in the DNS
and
this flag is set, a non-zero error code is returned.
If the hostname is not found and the flag is not set, the
address is returned in numeric form.
</p></dd>
<dt><span class="term"><code class="constant">NI_NUMERICSERV</code></span></dt>
<dd><p>
The service name is returned as a digit string representing the
port number.
</p></dd>
<dt><span class="term"><code class="constant">NI_DGRAM</code></span></dt>
<dd><p>
Specifies that the service being looked up is a datagram
service, and causes getservbyport() to be called with a second
argument of "udp" instead of its default of "tcp". This is
required
for the few ports (512-514) that have different services for UDP
and
TCP.
</p></dd>
</dl></div>
<p>
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2525344"></a><h2>RETURN VALUES</h2>
<p><code class="function">lwres_getnameinfo()</code>
returns 0 on success or a non-zero error code if an error occurs.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2525355"></a><h2>SEE ALSO</h2>
<p><span class="citerefentry"><span class="refentrytitle">RFC2133</span></span>,
<span class="citerefentry"><span class="refentrytitle">getservbyport</span>(3)</span>,
<span class="citerefentry"><span class="refentrytitle">lwres</span>(3)</span>,
<span class="citerefentry"><span class="refentrytitle">lwres_getnameinfo</span>(3)</span>,
<span class="citerefentry"><span class="refentrytitle">lwres_getnamebyaddr</span>(3)</span>.
<span class="citerefentry"><span class="refentrytitle">lwres_net_ntop</span>(3)</span>.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2525413"></a><h2>BUGS</h2>
<p>
RFC2133 fails to define what the nonzero return values of
<span class="citerefentry"><span class="refentrytitle">getnameinfo</span>(3)</span>
are.
</p>
</div>
</div></body>
</html>