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<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en">
<a name="id2482688"></a><div class="titlepage"></div>
<div class="refnamediv">
<h2>Name</h2>
<p>lwres_getnameinfo — lightweight resolver socket address structure to hostname and service name</p>
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<div class="refsynopsisdiv">
<h2>Synopsis</h2>
<div class="funcsynopsis">
<pre class="funcsynopsisinfo">#include <lwres/netdb.h></pre>
<table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0">
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<td><code class="funcdef">
int
<b class="fsfunc">lwres_getnameinfo</b>(</code></td>
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<td>
<code>)</code>;</td>
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<div class="refsect1" lang="en">
<a name="id2549427"></a><h2>DESCRIPTION</h2>
<p> This function is equivalent to the <span class="citerefentry"><span class="refentrytitle">getnameinfo</span>(3)</span> function defined in RFC2133.
<code class="function">lwres_getnameinfo()</code> returns the hostname for the
<span class="type">struct sockaddr</span> <em class="parameter"><code>sa</code></em> which is
<em class="parameter"><code>salen</code></em> bytes long. The hostname is of length
<em class="parameter"><code>hostlen</code></em> and is returned via
<em class="parameter"><code>*host.</code></em> The maximum length of the hostname is
1025 bytes: <code class="constant">NI_MAXHOST</code>.</p>
<p> The name of the service associated with the port number in
<em class="parameter"><code>sa</code></em> is returned in <em class="parameter"><code>*serv.</code></em>
It is <em class="parameter"><code>servlen</code></em> bytes long. The maximum length
of the service name is <code class="constant">NI_MAXSERV</code> - 32 bytes.
</p>
<p> The <em class="parameter"><code>flags</code></em> argument sets the following
bits:
</p>
<div class="variablelist"><dl>
<dt><span class="term"><code class="constant">NI_NOFQDN</code></span></dt>
<dd><p>
A fully qualified domain name is not required for local hosts.
The local part of the fully qualified domain name is returned instead.
</p></dd>
<dt><span class="term"><code class="constant">NI_NUMERICHOST</code></span></dt>
<dd><p>
Return the address in numeric form, as if calling inet_ntop(),
instead of a host name.
</p></dd>
<dt><span class="term"><code class="constant">NI_NAMEREQD</code></span></dt>
<dd><p>
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="id2549553"></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="id2549634"></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="id2549692"></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>
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