man/sd_id128_randomize.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4
   5 <!--
   6   SPDX-License-Identifier: LGPL-2.1+
   7 -->
   8
   9 <refentry id="sd_id128_randomize" xmlns:xi="http://www.w3.org/2001/XInclude">
  10
  11   <refentryinfo>
  12     <title>sd_id128_randomize</title>
  13     <productname>elogind</productname>
  14   </refentryinfo>
  15
  16   <refmeta>
  17     <refentrytitle>sd_id128_randomize</refentrytitle>
  18     <manvolnum>3</manvolnum>
  19   </refmeta>
  20
  21   <refnamediv>
  22     <refname>sd_id128_randomize</refname>
  23     <refpurpose>Generate 128-bit IDs</refpurpose>
  24   </refnamediv>
  25
  26   <refsynopsisdiv>
  27     <funcsynopsis>
  28       <funcsynopsisinfo>#include &lt;elogind/sd-id128.h&gt;</funcsynopsisinfo>
  29
  30       <funcprototype>
  31         <funcdef>int <function>sd_id128_randomize</function></funcdef>
  32         <paramdef>sd_id128_t *<parameter>ret</parameter></paramdef>
  33       </funcprototype>
  34
  35     </funcsynopsis>
  36   </refsynopsisdiv>
  37
  38   <refsect1>
  39     <title>Description</title>
  40
  41     <para><function>sd_id128_randomize()</function> generates a new
  42     randomized 128-bit ID and returns it in
  43     <parameter>ret</parameter>. Every invocation returns a new
  44     randomly generated ID. This uses the
  45     <filename>/dev/urandom</filename> kernel random number
  46     generator.</para>
  47
  48     <para>Note that <function>sd_id128_randomize()</function> always
  49     returns a UUID v4-compatible ID.</para>
  50
  51     <para>For more information about the <literal>sd_id128_t</literal>
  52     type, see
  53     <citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
  54
  55 <!-- 0 /// elogind does not support journalctl
  56     <para><citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
  57     <option>&#x2D;&#x2D;new-id128</option> option may be used as a command line
  58     front-end for <function>sd_id128_randomize()</function>.</para>
  59 // 0 -->
  60   </refsect1>
  61
  62   <refsect1>
  63     <title>Return Value</title>
  64
  65     <para>The call returns 0 on success (in which case
  66     <parameter>ret</parameter> is filled in), or a negative
  67     errno-style error code.</para>
  68   </refsect1>
  69
  70   <xi:include href="libelogind-pkgconfig.xml" />
  71
  72   <refsect1>
  73     <title>See Also</title>
  74
  75     <para>
  76       <!-- 0 /// elogind is in section 8
  77       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  78       --><!-- else -->
  79       <citerefentry><refentrytitle>elogind</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
  80       <!-- // 0 -->
  81       <citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
  82       <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
  83       <citerefentry><refentrytitle>random</refentrytitle><manvolnum>4</manvolnum></citerefentry>,
  84       <citerefentry><refentrytitle>sd_id128_get_machine</refentrytitle><manvolnum>3</manvolnum></citerefentry>
  85     </para>
  86   </refsect1>
  87
  88 </refentry>