136 lines
4.4 KiB
HTML
136 lines
4.4 KiB
HTML
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
|
||
|
|
<html><head>
|
||
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
||
|
|
<meta name="Copyright" content="Copyright (c) 2006 by IBM Corporation">
|
||
|
|
<title>if_nametoindex--Map an Interface Name to its Corresponding Index API</title>
|
||
|
|
<!-- Begin Header Records -->
|
||
|
|
<!-- All rights reserved. Licensed Materials Property of IBM -->
|
||
|
|
<!-- US Government Users Restricted Rights -->
|
||
|
|
<!-- Use, duplication or disclosure restricted by -->
|
||
|
|
<!-- GSA ADP Schedule Contract with IBM Corp. -->
|
||
|
|
<!-- Change History: -->
|
||
|
|
<!-- YYMMDD USERID Change description -->
|
||
|
|
<!-- Created for V5R4 by Tim Mullenbach -->
|
||
|
|
|
||
|
|
<link rel="stylesheet" type="text/css" href="../rzahg/ic.css">
|
||
|
|
|
||
|
|
</head>
|
||
|
|
<body>
|
||
|
|
<!-- End Header Records -->
|
||
|
|
<!-- Java sync-link -->
|
||
|
|
<script type="text/javascript" language="Javascript" src="../rzahg/synch.js">
|
||
|
|
</script>
|
||
|
|
|
||
|
|
<a name="Top_Of_Page"></a>
|
||
|
|
<h2><img src="delta.gif" ALT="Start of change">if_nametoindex()--Map an
|
||
|
|
Interface Name to its Corresponding Index</h2>
|
||
|
|
<div class="box" style="width: 70%;">
|
||
|
|
<br>
|
||
|
|
<br>
|
||
|
|
Syntax
|
||
|
|
<pre>
|
||
|
|
#include <net/if.h>
|
||
|
|
|
||
|
|
unsigned int if_nametoindex(const char *ifname);
|
||
|
|
|
||
|
|
</pre>
|
||
|
|
Service Program Name: QSOSRV2
|
||
|
|
<br>
|
||
|
|
Default Public Authority: *USE
|
||
|
|
<br>
|
||
|
|
Threadsafe: Yes<br><br>
|
||
|
|
</div>
|
||
|
|
|
||
|
|
<p>The <strong><em>if_nametoindex()</em></strong> function
|
||
|
|
returns the interface index corresponding to name <em>ifname</em>.</p>
|
||
|
|
<br>
|
||
|
|
<h3><a name="Header_2">Parameters</a></h3>
|
||
|
|
<dl>
|
||
|
|
<dt><strong><em>ifname</em></strong> (Input) </dt>
|
||
|
|
<dd>Pointer to a null terminated string containing the interface (line
|
||
|
|
description) name.<br><br></dd>
|
||
|
|
</dl>
|
||
|
|
<br>
|
||
|
|
<h3><a name="Header_3">Authorities</a></h3>
|
||
|
|
<p>
|
||
|
|
No authorization is required.</p>
|
||
|
|
<br>
|
||
|
|
<h3><a name="Header_4">Return Value</a></h3>
|
||
|
|
<p><em>if_nametoindex()</em> returns an unsigned integer. Possible values are:</p>
|
||
|
|
<ul>
|
||
|
|
<li>n (where n is the corresponding index value)</li>
|
||
|
|
<li>0 (unsuccessful)</li>
|
||
|
|
</ul>
|
||
|
|
<br>
|
||
|
|
<h3><a name="Header_5">Error Conditions</a></h3>
|
||
|
|
<p>When <em>if_nametoindex()</em> fails, <em>errno</em> can be set to one of the following:</p>
|
||
|
|
<dl compact>
|
||
|
|
<dt><em>[ENXIO]</em></dt>
|
||
|
|
<dd>The specified interface name does not exist.</dd>
|
||
|
|
<dt><em>[EFAULT]</em></dt>
|
||
|
|
<dd>The buffer pointed to by <em>ifname</em> can not be accessed.</dd>
|
||
|
|
</dl>
|
||
|
|
<br>
|
||
|
|
<h3>Usage Notes</h3>
|
||
|
|
<ol>
|
||
|
|
<li>
|
||
|
|
The interface (line description) name found at <em>ifname</em> is assumed to
|
||
|
|
be in the default coded character set identifier (CCSID) currently in effect
|
||
|
|
for the job.</li>
|
||
|
|
<li>It is important to note that the term "Interface" refers to the name on a line
|
||
|
|
description (i.e. a physical interface) for this API. Other parts of the
|
||
|
|
operating system, when refering to "Interface," mean an IP address.</li>
|
||
|
|
</ol>
|
||
|
|
<br>
|
||
|
|
<h3><a name="Header_8">Related Information</a></h3>
|
||
|
|
<ul>
|
||
|
|
<li><a href="gsocko.htm">getsockopt()</a>--Retrieve Information about Socket Options</li>
|
||
|
|
<li><a href="if_freenameindex.htm">if_freenameindex()</a>--Free Memory Allocated by
|
||
|
|
if_nameindex()</li>
|
||
|
|
<li><a href="if_indextoname.htm">if_indextoname()</a>--Map an Interface Index to its
|
||
|
|
Corresponding Name</li>
|
||
|
|
<li><a href="if_nameindex.htm">if_nameindex()</a>--Return All Interface Names and Indexes</li>
|
||
|
|
<li><a href="ssocko.htm">setsockopt()</a>--Set Socket Options</li>
|
||
|
|
</ul>
|
||
|
|
<br>
|
||
|
|
<h3><a name="Header_9">Example</a></h3>
|
||
|
|
<p>See <a href="../apiref/aboutapis.htm#codedisclaimer">Code disclaimer information</a>
|
||
|
|
for information pertaining to code examples.</p>
|
||
|
|
<p>The following example shows how <strong>if_nametoindex()</strong> is used:</p>
|
||
|
|
<pre>
|
||
|
|
#include <net/if.h>
|
||
|
|
#include <sys/types.h>
|
||
|
|
#include <errno.h>
|
||
|
|
|
||
|
|
void main()
|
||
|
|
{
|
||
|
|
|
||
|
|
<strong>unsigned int interfaceIndex = if_nametoindex("MYETH");</strong>
|
||
|
|
if (interfaceIndex == 0)
|
||
|
|
{
|
||
|
|
printf("if_nametoindex() failed with errno = %d %s \n",
|
||
|
|
errno,strerror(errno));
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
...
|
||
|
|
|
||
|
|
}</pre>
|
||
|
|
<img src="deltaend.gif" ALT="End of change">
|
||
|
|
<br>
|
||
|
|
<hr>
|
||
|
|
API introduced: V5R4
|
||
|
|
<hr>
|
||
|
|
<center>
|
||
|
|
<table cellpadding=2 cellspacing=2>
|
||
|
|
<tr align=center><td valign=middle align=center>
|
||
|
|
<a href="#Top_Of_Page">Top</a> |
|
||
|
|
<a href="unix.htm">UNIX-Type APIs</a> |
|
||
|
|
<a href="aplist.htm">APIs by category</a>
|
||
|
|
</td></tr>
|
||
|
|
</table>
|
||
|
|
</center>
|
||
|
|
</body>
|
||
|
|
</html>
|
||
|
|
|