man/sd_machine_get_class.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4 <!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
   5
   6 <refentry id="sd_machine_get_class" xmlns:xi="http://www.w3.org/2001/XInclude">
   7
   8   <refentryinfo>
   9     <title>sd_machine_get_class</title>
  10     <productname>systemd</productname>
  11   </refentryinfo>
  12
  13   <refmeta>
  14     <refentrytitle>sd_machine_get_class</refentrytitle>
  15     <manvolnum>3</manvolnum>
  16   </refmeta>
  17
  18   <refnamediv>
  19     <refname>sd_machine_get_class</refname>
  20     <refname>sd_machine_get_ifindices</refname>
  21     <refpurpose>Determine the class and network interface indices of a
  22     locally running virtual machine or container</refpurpose>
  23   </refnamediv>
  24
  25   <refsynopsisdiv>
  26     <funcsynopsis>
  27       <funcsynopsisinfo>#include &lt;systemd/sd-login.h&gt;</funcsynopsisinfo>
  28
  29       <funcprototype>
  30         <funcdef>int <function>sd_machine_get_class</function></funcdef>
  31         <paramdef>const char* <parameter>machine</parameter></paramdef>
  32         <paramdef>char **<parameter>class</parameter></paramdef>
  33       </funcprototype>
  34
  35       <funcprototype>
  36         <funcdef>int <function>sd_machine_get_ifindices</function></funcdef>
  37         <paramdef>const char* <parameter>machine</parameter></paramdef>
  38         <paramdef>int **<parameter>ret_ifindices</parameter></paramdef>
  39       </funcprototype>
  40     </funcsynopsis>
  41   </refsynopsisdiv>
  42
  43   <refsect1>
  44     <title>Description</title>
  45
  46     <para><function>sd_machine_get_class()</function> may be used to
  47     determine the class of a locally running virtual machine or
  48     container that is registered with
  49     <citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
  50     The string returned is either <literal>vm</literal> or
  51     <literal>container</literal>. The returned string needs to be
  52     freed with the libc <citerefentry
  53     project='man-pages'><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
  54     call after use.</para>
  55
  56     <para><function>sd_machine_get_ifindices()</function> may be used to determine the numeric indices of the
  57     network interfaces on the host that are pointing towards the specified locally running virtual machine or
  58     container. The vm or container must be registered with
  59     <citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
  60     The output parameter <parameter>ret_ifindices</parameter> may be passed as <constant>NULL</constant> when
  61     the output value is not needed. The returned array needs to be freed with the libc <citerefentry
  62     project='man-pages'><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry> call after
  63     use.</para>
  64   </refsect1>
  65
  66   <refsect1>
  67     <title>Return Value</title>
  68
  69     <para>On success, these functions return a non-negative integer.
  70     <function>sd_machine_get_ifindices()</function> returns the number of the relevant network interfaces.
  71     On failure, these calls return a negative errno-style error code.</para>
  72
  73     <refsect2>
  74       <title>Errors</title>
  75
  76       <para>Returned errors may indicate the following problems:</para>
  77
  78       <variablelist>
  79
  80         <varlistentry>
  81           <term><constant>-ENXIO</constant></term>
  82
  83           <listitem><para>The specified machine does not exist or is currently not running.</para>
  84           </listitem>
  85         </varlistentry>
  86
  87         <varlistentry>
  88           <term><constant>-EINVAL</constant></term>
  89
  90           <listitem><para>An input parameter was invalid (out of range, or <constant>NULL</constant>, where
  91           that is not accepted).</para></listitem>
  92         </varlistentry>
  93
  94         <varlistentry>
  95           <term><constant>-ENOMEM</constant></term>
  96
  97           <listitem><para>Memory allocation failed.</para></listitem>
  98         </varlistentry>
  99       </variablelist>
 100     </refsect2>
 101   </refsect1>
 102
 103   <xi:include href="libsystemd-pkgconfig.xml" />
 104
 105   <refsect1>
 106     <title>History</title>
 107     <para><function>sd_machine_get_class()</function> and
 108     <function>sd_machine_get_ifindices()</function> were added in version 217.</para>
 109   </refsect1>
 110
 111   <refsect1>
 112     <title>See Also</title>
 113
 114     <para>
 115       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 116       <citerefentry><refentrytitle>sd-login</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 117       <citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 118       <citerefentry><refentrytitle>sd_pid_get_machine_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 119     </para>
 120   </refsect1>
 121
 122 </refentry>