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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 f2f8af0eb5..0000000000 --- a/man/sd_journal_query_unique.xml +++ /dev/null @@ -1,214 +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 '='.</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 shared library, which can - be compiled and linked to with the - <literal>libsystemd-journal</literal> - <citerefentry><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> |