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diff --git a/lib/lwres/man/lwres_getaddrinfo.html b/lib/lwres/man/lwres_getaddrinfo.html new file mode 100644 index 0000000..786a811 --- /dev/null +++ b/lib/lwres/man/lwres_getaddrinfo.html @@ -0,0 +1,374 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<!-- + - Copyright (C) 2000, 2001, 2003-2005, 2007, 2014-2016, 2018, 2019 Internet Systems Consortium, Inc. ("ISC") + - + - This Source Code Form is subject to the terms of the Mozilla Public + - License, v. 2.0. If a copy of the MPL was not distributed with this + - file, You can obtain one at http://mozilla.org/MPL/2.0/. +--> +<html lang="en"> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>lwres_getaddrinfo</title> +<meta name="generator" content="DocBook XSL Stylesheets V1.78.1"> +</head> +<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry"> +<a name="id-1"></a><div class="titlepage"></div> + + + + + + + + <div class="refnamediv"> +<h2>Name</h2> +<p> + lwres_getaddrinfo, + lwres_freeaddrinfo + — socket address structure to host and service name + </p> +</div> + <div class="refsynopsisdiv"> +<h2>Synopsis</h2> + <div class="funcsynopsis"> +<pre class="funcsynopsisinfo">#include <lwres/netdb.h></pre> +<table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"> +<tr> +<td><code class="funcdef"> +int +<b class="fsfunc">lwres_getaddrinfo</b>(</code></td> +<td>const char *<var class="pdparam">hostname</var>, </td> +</tr> +<tr> +<td> </td> +<td>const char *<var class="pdparam">servname</var>, </td> +</tr> +<tr> +<td> </td> +<td>const struct addrinfo *<var class="pdparam">hints</var>, </td> +</tr> +<tr> +<td> </td> +<td>struct addrinfo **<var class="pdparam">res</var><code>)</code>;</td> +</tr> +</table> +<div class="funcprototype-spacer"> </div> +<table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr> +<td><code class="funcdef"> +void +<b class="fsfunc">lwres_freeaddrinfo</b>(</code></td> +<td>struct addrinfo *<var class="pdparam">ai</var><code>)</code>;</td> +</tr></table> +<div class="funcprototype-spacer"> </div> +</div> + + <p> + If the operating system does not provide a + <span class="type">struct addrinfo</span>, + the following structure is used: + </p> + <pre class="programlisting"> +struct addrinfo { + int ai_flags; /* AI_PASSIVE, AI_CANONNAME */ + int ai_family; /* PF_xxx */ + int ai_socktype; /* SOCK_xxx */ + int ai_protocol; /* 0 or IPPROTO_xxx for IPv4 and IPv6 */ + size_t ai_addrlen; /* length of ai_addr */ + char *ai_canonname; /* canonical name for hostname */ + struct sockaddr *ai_addr; /* binary address */ + struct addrinfo *ai_next; /* next structure in linked list */ +}; +</pre> +<p> + </p> + + </div> + + <div class="refsection"> +<a name="id-1.7"></a><h2>DESCRIPTION</h2> + + + <p><code class="function">lwres_getaddrinfo()</code> + is used to get a list of IP addresses and port numbers for host + <em class="parameter"><code>hostname</code></em> and service + <em class="parameter"><code>servname</code></em>. + + The function is the lightweight resolver's implementation of + <code class="function">getaddrinfo()</code> as defined in RFC2133. + <em class="parameter"><code>hostname</code></em> and + <em class="parameter"><code>servname</code></em> are pointers to null-terminated + strings or <span class="type">NULL</span>. + + <em class="parameter"><code>hostname</code></em> is either a host name or a + numeric host address string: a dotted decimal IPv4 address or an + IPv6 address. <em class="parameter"><code>servname</code></em> is either a + decimal port number or a service name as listed in + <code class="filename">/etc/services</code>. + </p> + + <p><em class="parameter"><code>hints</code></em> + is an optional pointer to a + <span class="type">struct addrinfo</span>. + This structure can be used to provide hints concerning the type of + socket + that the caller supports or wishes to use. + The caller can supply the following structure elements in + <em class="parameter"><code>*hints</code></em>: + + </p> +<div class="variablelist"><dl class="variablelist"> +<dt><span class="term"><code class="constant">ai_family</code></span></dt> +<dd> + <p> + The protocol family that should be used. + When + <code class="constant">ai_family</code> + is set to + <span class="type">PF_UNSPEC</span>, + it means the caller will accept any protocol family supported by + the + operating system. + </p> + </dd> +<dt><span class="term"><code class="constant">ai_socktype</code></span></dt> +<dd> + <p> + denotes the type of socket — + <span class="type">SOCK_STREAM</span>, + <span class="type">SOCK_DGRAM</span> + or + <span class="type">SOCK_RAW</span> + — that is wanted. + When + <code class="constant">ai_socktype</code> + is zero the caller will accept any socket type. + </p> + </dd> +<dt><span class="term"><code class="constant">ai_protocol</code></span></dt> +<dd> + <p> + indicates which transport protocol is wanted: IPPROTO_UDP or + IPPROTO_TCP. + If + <code class="constant">ai_protocol</code> + is zero the caller will accept any protocol. + </p> + </dd> +<dt><span class="term"><code class="constant">ai_flags</code></span></dt> +<dd> + <p> + Flag bits. + If the + <span class="type">AI_CANONNAME</span> + bit is set, a successful call to + <code class="function">lwres_getaddrinfo()</code> + will return a null-terminated string containing the canonical + name + of the specified hostname in + <code class="constant">ai_canonname</code> + of the first + <span class="type">addrinfo</span> + structure returned. + Setting the + <span class="type">AI_PASSIVE</span> + bit indicates that the returned socket address structure is + intended + for used in a call to + <span class="citerefentry"> + <span class="refentrytitle">bind</span>(2) + </span>. + + In this case, if the hostname argument is a + <span class="type">NULL</span> + pointer, then the IP address portion of the socket + address structure will be set to + <span class="type">INADDR_ANY</span> + for an IPv4 address or + <span class="type">IN6ADDR_ANY_INIT</span> + for an IPv6 address. + </p> + <p> + When + <code class="constant">ai_flags</code> + does not set the + <span class="type">AI_PASSIVE</span> + bit, the returned socket address structure will be ready + for use in a call to + <span class="citerefentry"> + <span class="refentrytitle">connect</span>(2) + </span> + for a connection-oriented protocol or + <span class="citerefentry"> + <span class="refentrytitle">connect</span>(2) + </span>, + + <span class="citerefentry"> + <span class="refentrytitle">sendto</span>(2) + </span>, + + or + <span class="citerefentry"> + <span class="refentrytitle">sendmsg</span>(2) + </span> + if a connectionless protocol was chosen. + The IP address portion of the socket address structure will be + set to the loopback address if + <em class="parameter"><code>hostname</code></em> + is a + <span class="type">NULL</span> + pointer and + <span class="type">AI_PASSIVE</span> + is not set in + <code class="constant">ai_flags</code>. + </p> + <p> + If + <code class="constant">ai_flags</code> + is set to + <span class="type">AI_NUMERICHOST</span> + it indicates that + <em class="parameter"><code>hostname</code></em> + should be treated as a numeric string defining an IPv4 or IPv6 + address + and no name resolution should be attempted. + </p> + </dd> +</dl></div> +<p> + </p> + + <p> + All other elements of the <span class="type">struct addrinfo</span> passed + via <em class="parameter"><code>hints</code></em> must be zero. + </p> + + <p> + A <em class="parameter"><code>hints</code></em> of <span class="type">NULL</span> is + treated as if + the caller provided a <span class="type">struct addrinfo</span> initialized to zero + with <code class="constant">ai_family</code>set to + <code class="constant">PF_UNSPEC</code>. + </p> + + <p> + After a successful call to + <code class="function">lwres_getaddrinfo()</code>, + <em class="parameter"><code>*res</code></em> + is a pointer to a linked list of one or more + <span class="type">addrinfo</span> + structures. + Each + <span class="type">struct addrinfo</span> + in this list cn be processed by following + the + <code class="constant">ai_next</code> + pointer, until a + <span class="type">NULL</span> + pointer is encountered. + The three members + <code class="constant">ai_family</code>, + <code class="constant">ai_socktype</code>, + and + <code class="constant">ai_protocol</code> + in each + returned + <span class="type">addrinfo</span> + structure contain the corresponding arguments for a call to + <span class="citerefentry"> + <span class="refentrytitle">socket</span>(2) + </span>. + For each + <span class="type">addrinfo</span> + structure in the list, the + <code class="constant">ai_addr</code> + member points to a filled-in socket address structure of length + <code class="constant">ai_addrlen</code>. + </p> + + <p> + All of the information returned by + <code class="function">lwres_getaddrinfo()</code> + is dynamically allocated: the addrinfo structures, and the socket + address structures and canonical host name strings pointed to by the + <code class="constant">addrinfo</code>structures. + Memory allocated for the dynamically allocated structures created by + a successful call to + <code class="function">lwres_getaddrinfo()</code> + is released by + <code class="function">lwres_freeaddrinfo()</code>. + <em class="parameter"><code>ai</code></em> + is a pointer to a + <span class="type">struct addrinfo</span> + created by a call to + <code class="function">lwres_getaddrinfo()</code>. + </p> + + </div> + + <div class="refsection"> +<a name="id-1.8"></a><h2>RETURN VALUES</h2> + + + <p><code class="function">lwres_getaddrinfo()</code> + returns zero on success or one of the error codes listed in + <span class="citerefentry"> + <span class="refentrytitle">gai_strerror</span>(3) + </span> + if an error occurs. If both <em class="parameter"><code>hostname</code></em> and + <em class="parameter"><code>servname</code></em> are <span class="type">NULL</span> + <code class="function">lwres_getaddrinfo()</code> returns + <span class="errorcode">EAI_NONAME</span>. + </p> + </div> + <div class="refsection"> +<a name="id-1.9"></a><h2>SEE ALSO</h2> + + <p><span class="citerefentry"> + <span class="refentrytitle">lwres</span>(3) + </span>, + + <span class="citerefentry"> + <span class="refentrytitle">lwres_getaddrinfo</span>(3) + </span>, + + <span class="citerefentry"> + <span class="refentrytitle">lwres_freeaddrinfo</span>(3) + </span>, + + <span class="citerefentry"> + <span class="refentrytitle">lwres_gai_strerror</span>(3) + </span>, + + <span class="citerefentry"> + <span class="refentrytitle">RFC2133</span> + </span>, + + <span class="citerefentry"> + <span class="refentrytitle">getservbyname</span>(3) + </span>, + + <span class="citerefentry"> + <span class="refentrytitle">bind</span>(2) + </span>, + + <span class="citerefentry"> + <span class="refentrytitle">connect</span>(2) + </span>, + + <span class="citerefentry"> + <span class="refentrytitle">sendto</span>(2) + </span>, + + <span class="citerefentry"> + <span class="refentrytitle">sendmsg</span>(2) + </span>, + + <span class="citerefentry"> + <span class="refentrytitle">socket</span>(2) + </span>. + </p> + + </div> +</div></body> +</html> |