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diff --git a/man/sd_journal_query_unique.xml b/man/sd_journal_query_unique.xml deleted file mode 100644 index ac0e5f633..000000000 --- a/man/sd_journal_query_unique.xml +++ /dev/null @@ -1,206 +0,0 @@ -<?xml version='1.0'?> <!--*-nxml-*--> -<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" - "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> - -<!-- - This file is part of systemd. - - Copyright 2012 Lennart Poettering - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. ---> - -<refentry id="sd_journal_query_unique"> - - <refentryinfo> - <title>sd_journal_query_unique</title> - <productname>systemd</productname> - - <authorgroup> - <author> - <contrib>Developer</contrib> - <firstname>Lennart</firstname> - <surname>Poettering</surname> - <email>lennart@poettering.net</email> - </author> - </authorgroup> - </refentryinfo> - - <refmeta> - <refentrytitle>sd_journal_query_unique</refentrytitle> - <manvolnum>3</manvolnum> - </refmeta> - - <refnamediv> - <refname>sd_journal_query_unique</refname> - <refname>sd_journal_enumerate_unique</refname> - <refname>sd_journal_restart_unique</refname> - <refname>SD_JOURNAL_FOREACH_UNIQUE</refname> - <refpurpose>Read unique data fields from the journal</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcsynopsisinfo>#include <systemd/sd-journal.h></funcsynopsisinfo> - - <funcprototype> - <funcdef>int <function>sd_journal_query_unique</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - <paramdef>const char *<parameter>field</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_journal_enumerate_unique</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - <paramdef>const void **<parameter>data</parameter></paramdef> - <paramdef>size_t *<parameter>length</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>void <function>sd_journal_restart_unique</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef><function>SD_JOURNAL_FOREACH_UNIQUE</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - <paramdef>const void *<parameter>data</parameter></paramdef> - <paramdef>size_t <parameter>length</parameter></paramdef> - </funcprototype> - - </funcsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - - <para><function>sd_journal_query_unique()</function> queries the - journal for all unique values the specified field can take. It - takes two arguments: the journal to query and the field name to - look for. Well-known field names are listed on - <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>. - Field names must be specified without a trailing '='. After this - function has been executed successfully the field values may be - queried using <function>sd_journal_enumerate_unique()</function>. - Invoking this call a second time will change the field name being - queried and reset the enumeration index to the first field value - that matches.</para> - - <para><function>sd_journal_enumerate_unique()</function> may be - used to iterate through all data fields which match the previously - selected field name as set with - <function>sd_journal_query_unique()</function>. On each invocation - the next field data matching the field name is returned. The order - of the returned data fields is not defined. It takes three - arguments: the journal context object, plus a pair of pointers to - pointer/size variables where the data object and its size shall be - stored in. The returned data is in a read-only memory map and is - only valid until the next invocation of - <function>sd_journal_enumerate_unique()</function>. Note that the - data returned will be prefixed with the field name and '='. Note - that this call is subject to the data field size threshold as - controlled by - <function>sd_journal_set_data_threshold()</function>.</para> - - <para><function>sd_journal_restart_unique()</function> resets the - data enumeration index to the beginning of the list. The next - invocation of <function>sd_journal_enumerate_unique()</function> - will return the first field data matching the field name - again.</para> - - <para>Note that the - <function>SD_JOURNAL_FOREACH_UNIQUE()</function> macro may be used - as a handy wrapper around - <function>sd_journal_restart_unique()</function> and - <function>sd_journal_enumerate_unique()</function>.</para> - - <para>Note that these functions currently are not influenced by - matches set with <function>sd_journal_add_match()</function> but - this might change in a later version of this software.</para> - </refsect1> - - <refsect1> - <title>Return Value</title> - - <para><function>sd_journal_query_unique()</function> returns 0 on - success or a negative errno-style error code. - <function>sd_journal_enumerate_unique()</function> returns a - positive integer if the next field data has been read, 0 when no - more fields are known, or a negative errno-style error code. - <function>sd_journal_restart_unique()</function> returns - nothing.</para> - </refsect1> - - <refsect1> - <title>Notes</title> - - <para>The <function>sd_journal_query_unique()</function>, - <function>sd_journal_enumerate_unique()</function> and - <function>sd_journal_restart_unique()</function> interfaces are - available as a shared library, which can be compiled and linked to - with the - <constant>libsystemd</constant> <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry> - file.</para> - </refsect1> - - <refsect1> - <title>Examples</title> - - <para>Use the <function>SD_JOURNAL_FOREACH_UNIQUE</function> macro - to iterate through all values a field of the journal can take. The - following example lists all unit names referenced in the - journal:</para> - - <programlisting>#include <stdio.h> -#include <string.h> -#include <systemd/sd-journal.h> - -int main(int argc, char *argv[]) { - sd_journal *j; - const void *d; - size_t l; - int r; - - r = sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY); - if (r < 0) { - fprintf(stderr, "Failed to open journal: %s\n", strerror(-r)); - return 1; - } - r = sd_journal_query_unique(j, "_SYSTEMD_UNIT"); - if (r < 0) { - fprintf(stderr, "Failed to query journal: %s\n", strerror(-r)); - return 1; - } - SD_JOURNAL_FOREACH_UNIQUE(j, d, l) - printf("%.*s\n", (int) l, (const char*) d); - sd_journal_close(j); - return 0; -}</programlisting> - - </refsect1> - - <refsect1> - <title>See Also</title> - - <para> - <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd-journal</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_journal_open</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_journal_get_data</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_journal_add_match</refentrytitle><manvolnum>3</manvolnum></citerefentry> - </para> - </refsect1> - -</refentry> |