man/sd_journal_get_cutoff_realtime_usec.xml

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   3   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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   5 <!--
   6   SPDX-License-Identifier: LGPL-2.1+
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   8
   9 <refentry id="sd_journal_get_cutoff_realtime_usec" xmlns:xi="http://www.w3.org/2001/XInclude">
  10
  11   <refentryinfo>
  12     <title>sd_journal_get_cutoff_realtime_usec</title>
  13     <productname>systemd</productname>
  14   </refentryinfo>
  15
  16   <refmeta>
  17     <refentrytitle>sd_journal_get_cutoff_realtime_usec</refentrytitle>
  18     <manvolnum>3</manvolnum>
  19   </refmeta>
  20
  21   <refnamediv>
  22     <refname>sd_journal_get_cutoff_realtime_usec</refname>
  23     <refname>sd_journal_get_cutoff_monotonic_usec</refname>
  24     <refpurpose>Read cut-off timestamps from the current journal entry</refpurpose>
  25   </refnamediv>
  26
  27   <refsynopsisdiv>
  28     <funcsynopsis>
  29       <funcsynopsisinfo>#include &lt;systemd/sd-journal.h&gt;</funcsynopsisinfo>
  30
  31       <funcprototype>
  32         <funcdef>int <function>sd_journal_get_cutoff_realtime_usec</function></funcdef>
  33         <paramdef>sd_journal *<parameter>j</parameter></paramdef>
  34         <paramdef>uint64_t *<parameter>from</parameter></paramdef>
  35         <paramdef>uint64_t *<parameter>to</parameter></paramdef>
  36       </funcprototype>
  37
  38       <funcprototype>
  39         <funcdef>int <function>sd_journal_get_cutoff_monotonic_usec</function></funcdef>
  40         <paramdef>sd_journal *<parameter>j</parameter></paramdef>
  41         <paramdef>sd_id128_t <parameter>boot_id</parameter></paramdef>
  42         <paramdef>uint64_t *<parameter>from</parameter></paramdef>
  43         <paramdef>uint64_t *<parameter>to</parameter></paramdef>
  44       </funcprototype>
  45
  46     </funcsynopsis>
  47   </refsynopsisdiv>
  48
  49   <refsect1>
  50     <title>Description</title>
  51
  52     <para><function>sd_journal_get_cutoff_realtime_usec()</function>
  53     retrieves the realtime (wallclock) timestamps of the first and
  54     last entries accessible in the journal. It takes three arguments:
  55     the journal context object <parameter>j</parameter> and two
  56     pointers <parameter>from</parameter> and <parameter>to</parameter>
  57     pointing at 64-bit unsigned integers to store the timestamps in.
  58     The timestamps are in microseconds since the epoch, i.e.
  59     <constant>CLOCK_REALTIME</constant>. Either one of the two
  60     timestamp arguments may be passed as <constant>NULL</constant> in
  61     case the timestamp is not needed, but not both.</para>
  62
  63     <para><function>sd_journal_get_cutoff_monotonic_usec()</function>
  64     retrieves the monotonic timestamps of the first and last entries
  65     accessible in the journal. It takes three arguments: the journal
  66     context object <parameter>j</parameter>, a 128-bit identifier for
  67     the boot <parameter>boot_id</parameter>, and two pointers to
  68     64-bit unsigned integers to store the timestamps,
  69     <parameter>from</parameter> and <parameter>to</parameter>. The
  70     timestamps are in microseconds since boot-up of the specific boot,
  71     i.e. <constant>CLOCK_MONOTONIC</constant>. Since the monotonic
  72     clock begins new with every reboot it only defines a well-defined
  73     point in time when used together with an identifier identifying
  74     the boot, see
  75     <citerefentry><refentrytitle>sd_id128_get_boot</refentrytitle><manvolnum>3</manvolnum></citerefentry>
  76     for more information. The function will return the timestamps for
  77     the boot identified by the passed boot ID. Either one of the two
  78     timestamp arguments may be passed as <constant>NULL</constant> in
  79     case the timestamp is not needed, but not both.</para>
  80   </refsect1>
  81
  82   <refsect1>
  83     <title>Return Value</title>
  84
  85     <para><function>sd_journal_get_cutoff_realtime_usec()</function>
  86     and <function>sd_journal_get_cutoff_monotonic_usec()</function>
  87     return 1 on success, 0 if not suitable entries are in the journal
  88     or a negative errno-style error code.</para>
  89
  90     <para>Locations pointed to by parameters
  91     <parameter>from</parameter> and <parameter>to</parameter> will be
  92     set only if the return value is positive, and obviously, the
  93     parameters are non-null.</para>
  94   </refsect1>
  95
  96   <refsect1>
  97     <title>Notes</title>
  98
  99     <xi:include href="threads-aware.xml" xpointer="strict" />
 100
 101     <xi:include href="libsystemd-pkgconfig.xml" xpointer="pkgconfig-text"/>
 102   </refsect1>
 103
 104   <refsect1>
 105     <title>See Also</title>
 106
 107     <para>
 108       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 109       <citerefentry><refentrytitle>sd-journal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 110       <citerefentry><refentrytitle>sd_journal_open</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 111       <citerefentry><refentrytitle>sd_journal_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 112       <citerefentry><refentrytitle>sd_id128_get_boot</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 113       <citerefentry><refentrytitle>clock_gettime</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 114     </para>
 115   </refsect1>
 116
 117 </refentry>