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   Copyright 2012 Lennart Poettering
   9 -->
  10
  11 <refentry id="sd_id128_randomize" xmlns:xi="http://www.w3.org/2001/XInclude">
  12
  13   <refentryinfo>
  14     <title>sd_id128_randomize</title>
  15     <productname>elogind</productname>
  16
  17     <authorgroup>
  18       <author>
  19         <contrib>Developer</contrib>
  20         <firstname>Lennart</firstname>
  21         <surname>Poettering</surname>
  22         <email>lennart@poettering.net</email>
  23       </author>
  24     </authorgroup>
  25   </refentryinfo>
  26
  27   <refmeta>
  28     <refentrytitle>sd_id128_randomize</refentrytitle>
  29     <manvolnum>3</manvolnum>
  30   </refmeta>
  31
  32   <refnamediv>
  33     <refname>sd_id128_randomize</refname>
  34     <refpurpose>Generate 128-bit IDs</refpurpose>
  35   </refnamediv>
  36
  37   <refsynopsisdiv>
  38     <funcsynopsis>
  39       <funcsynopsisinfo>#include &lt;elogind/sd-id128.h&gt;</funcsynopsisinfo>
  40
  41       <funcprototype>
  42         <funcdef>int <function>sd_id128_randomize</function></funcdef>
  43         <paramdef>sd_id128_t *<parameter>ret</parameter></paramdef>
  44       </funcprototype>
  45
  46     </funcsynopsis>
  47   </refsynopsisdiv>
  48
  49   <refsect1>
  50     <title>Description</title>
  51
  52     <para><function>sd_id128_randomize()</function> generates a new
  53     randomized 128-bit ID and returns it in
  54     <parameter>ret</parameter>. Every invocation returns a new
  55     randomly generated ID. This uses the
  56     <filename>/dev/urandom</filename> kernel random number
  57     generator.</para>
  58
  59     <para>Note that <function>sd_id128_randomize()</function> always
  60     returns a UUID v4-compatible ID.</para>
  61
  62     <para>For more information about the <literal>sd_id128_t</literal>
  63     type, see
  64     <citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
  65
  66 <!-- 0 /// elogind does not support journalctl
  67     <para><citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
  68     <option>&#x2D;&#x2D;new-id128</option> option may be used as a command line
  69     front-end for <function>sd_id128_randomize()</function>.</para>
  70 // 0 -->
  71   </refsect1>
  72
  73   <refsect1>
  74     <title>Return Value</title>
  75
  76     <para>The call returns 0 on success (in which case
  77     <parameter>ret</parameter> is filled in), or a negative
  78     errno-style error code.</para>
  79   </refsect1>
  80
  81   <xi:include href="libelogind-pkgconfig.xml" />
  82
  83   <refsect1>
  84     <title>See Also</title>
  85
  86     <para>
  87       <!-- 0 /// elogind is in section 8
  88       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  89       --><!-- else -->
  90       <citerefentry><refentrytitle>elogind</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
  91       <!-- // 0 -->
  92       <citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
  93       <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
  94       <citerefentry><refentrytitle>random</refentrytitle><manvolnum>4</manvolnum></citerefentry>,
  95       <citerefentry><refentrytitle>sd_id128_get_machine</refentrytitle><manvolnum>3</manvolnum></citerefentry>
  96     </para>
  97   </refsect1>
  98
  99 </refentry>