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diff --git a/man/sd_journal_get_data.xml b/man/sd_journal_get_data.xml deleted file mode 100644 index 1321114de0..0000000000 --- a/man/sd_journal_get_data.xml +++ /dev/null @@ -1,235 +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_get_data"> - - <refentryinfo> - <title>sd_journal_get_data</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_get_data</refentrytitle> - <manvolnum>3</manvolnum> - </refmeta> - - <refnamediv> - <refname>sd_journal_get_data</refname> - <refname>sd_journal_enumerate_data</refname> - <refname>sd_journal_restart_data</refname> - <refname>SD_JOURNAL_FOREACH_DATA</refname> - <refname>sd_journal_set_data_threshold</refname> - <refname>sd_journal_get_data_threshold</refname> - <refpurpose>Read data fields from the current journal entry</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcsynopsisinfo>#include <systemd/sd-journal.h></funcsynopsisinfo> - - <funcprototype> - <funcdef>int <function>sd_journal_get_data</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - <paramdef>const char *<parameter>field</parameter></paramdef> - <paramdef>const void **<parameter>data</parameter></paramdef> - <paramdef>size_t *<parameter>length</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_journal_enumerate_data</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_data</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef><function>SD_JOURNAL_FOREACH_DATA</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>int <function>sd_journal_set_data_threshold</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - <paramdef>size_t <parameter>sz</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_journal_get_data_threshold</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - <paramdef>size_t *<parameter>sz</parameter></paramdef> - </funcprototype> - </funcsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - - <para><function>sd_journal_get_data()</function> gets the data - object associated with a specific field from the current journal - entry. It takes four arguments: the journal context object, a - string with the field name to request, plus a pair of pointers to - pointer/size variables where the data object and its size shall be - stored in. The field name should be an entry field name. - Well-known field names are listed in - <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>. - The returned data is in a read-only memory map and is only valid - until the next invocation of - <function>sd_journal_get_data()</function> or - <function>sd_journal_enumerate_data()</function>, or the read - pointer is altered. Note that the data returned will be prefixed - with the field name and '='. Also note that, by default, data fields - larger than 64K might get truncated to 64K. This threshold may be - changed and turned off with - <function>sd_journal_set_data_threshold()</function> (see - below).</para> - - <para><function>sd_journal_enumerate_data()</function> may be used - to iterate through all fields of the current entry. On each - invocation the data for the next field is returned. The order of - these fields is not defined. The data returned is in the same - format as with <function>sd_journal_get_data()</function> and also - follows the same life-time semantics.</para> - - <para><function>sd_journal_restart_data()</function> resets the - data enumeration index to the beginning of the entry. The next - invocation of <function>sd_journal_enumerate_data()</function> - will return the first field of the entry again.</para> - - <para>Note that the <function>SD_JOURNAL_FOREACH_DATA()</function> - macro may be used as a handy wrapper around - <function>sd_journal_restart_data()</function> and - <function>sd_journal_enumerate_data()</function>.</para> - - <para>Note that these functions will not work before - <citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry> - (or related call) has been called at least once, in order to - position the read pointer at a valid entry.</para> - - <para><function>sd_journal_set_data_threshold()</function> may be - used to change the data field size threshold for data returned by - <function>sd_journal_get_data()</function>, - <function>sd_journal_enumerate_data()</function> and - <function>sd_journal_enumerate_unique()</function>. This threshold - is a hint only: it indicates that the client program is interested - only in the initial parts of the data fields, up to the threshold - in size — but the library might still return larger data objects. - That means applications should not rely exclusively on this - setting to limit the size of the data fields returned, but need to - apply an explicit size limit on the returned data as well. This - threshold defaults to 64K by default. To retrieve the complete - data fields this threshold should be turned off by setting it to - 0, so that the library always returns the complete data objects. - It is recommended to set this threshold as low as possible since - this relieves the library from having to decompress large - compressed data objects in full.</para> - - <para><function>sd_journal_get_data_threshold()</function> returns - the currently configured data field size threshold.</para> - </refsect1> - - <refsect1> - <title>Return Value</title> - - <para><function>sd_journal_get_data()</function> returns 0 on - success or a negative errno-style error code. If the current entry - does not include the specified field, -ENOENT is returned. If - <citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry> - has not been called at least once, -EADDRNOTAVAIL is returned. - <function>sd_journal_enumerate_data()</function> returns a - positive integer if the next field has been read, 0 when no more - fields are known, or a negative errno-style error code. - <function>sd_journal_restart_data()</function> returns nothing. - <function>sd_journal_set_data_threshold()</function> and - <function>sd_journal_get_threshold()</function> return 0 on - success or a negative errno-style error code.</para> - </refsect1> - - <refsect1> - <title>Notes</title> - - <para>The <function>sd_journal_get_data()</function>, - <function>sd_journal_enumerate_data()</function>, - <function>sd_journal_restart_data()</function>, - <function>sd_journal_set_data_threshold()</function> and - <function>sd_journal_get_data_threshold()</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>See - <citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry> - for a complete example how to use - <function>sd_journal_get_data()</function>.</para> - - <para>Use the - <function>SD_JOURNAL_FOREACH_DATA</function> macro to - iterate through all fields of the current journal - entry:</para> - - <programlisting>... -int print_fields(sd_journal *j) { - const void *data; - size_t length; - SD_JOURNAL_FOREACH_DATA(j, data, length) - printf("%.*s\n", (int) length, data); -} -...</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_next</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_journal_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_journal_query_unique</refentrytitle><manvolnum>3</manvolnum></citerefentry> - </para> - </refsect1> - -</refentry> |