sd_id128_randomize.xml revision 12b42c76672a66c2d4ea7212c14f8f1b5a62b78d
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
12b42c76672a66c2d4ea7212c14f8f1b5a62b78dTom Gundersen "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering This file is part of systemd.
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering Copyright 2012 Lennart Poettering
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering systemd is free software; you can redistribute it and/or modify it
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering under the terms of the GNU Lesser General Public License as published by
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering the Free Software Foundation; either version 2.1 of the License, or
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering (at your option) any later version.
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering systemd is distributed in the hope that it will be useful, but
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering WITHOUT ANY WARRANTY; without even the implied warranty of
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering Lesser General Public License for more details.
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering You should have received a copy of the GNU Lesser General Public License
12355095821fc17529af5b6eaefa31c3c520be39Lennart Poettering along with systemd; If not, see <http://www.gnu.org/licenses/>.
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <title>sd_id128_randomize</title>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <productname>systemd</productname>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <email>lennart@poettering.net</email>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <refentrytitle>sd_id128_randomize</refentrytitle>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <refname>sd_id128_randomize</refname>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <refpurpose>Generate 128-bit IDs</refpurpose>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <refsynopsisdiv>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <funcsynopsisinfo>#include <systemd/sd-id128.h></funcsynopsisinfo>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <funcdef>int <function>sd_id128_randomize</function></funcdef>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <paramdef>sd_id128_t *<parameter>ret</parameter></paramdef>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek </funcprototype>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek </refsynopsisdiv>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <para><function>sd_id128_randomize()</function> generates a new
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek randomized 128-bit ID and returns it in
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <parameter>ret</parameter>. Every invocation returns a new
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek randomly generated ID. This uses the
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <filename>/dev/urandom</filename> kernel random number
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek generator.</para>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <para>Note that <function>sd_id128_randomize()</function> always
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek returns a UUID v4-compatible ID.</para>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <para>For more information about the <literal>sd_id128_t</literal>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <para><citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <option>--new-id</option> option may be used as a command line
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek front-end for <function>sd_id128_randomize()</function>.</para>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <para>The call returns 0 on success (in which case
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <parameter>ret</parameter> is filled in), or a negative
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek errno-style error code.</para>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <para>The <function>sd_id128_randomize()</function> interface is
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek available as a shared library, which can be compiled and linked to
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <literal>libsystemd</literal> <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <citerefentry><refentrytitle>random</refentrytitle><manvolnum>4</manvolnum></citerefentry>,
798d3a524ea57aaf40cb53858aaa45ec702f012dZbigniew Jędrzejewski-Szmek <citerefentry><refentrytitle>sd_id128_get_machine</refentrytitle><manvolnum>3</manvolnum></citerefentry>