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diff --git a/man/sd_journal_get_data_threshold.html b/man/sd_journal_get_data_threshold.html deleted file mode 100644 index adc77e6c36..0000000000 --- a/man/sd_journal_get_data_threshold.html +++ /dev/null @@ -1,110 +0,0 @@ -<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>sd_journal_get_data</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><style> - a.headerlink { - color: #c60f0f; - font-size: 0.8em; - padding: 0 4px 0 4px; - text-decoration: none; - visibility: hidden; - } - - a.headerlink:hover { - background-color: #c60f0f; - color: white; - } - - h1:hover > a.headerlink, h2:hover > a.headerlink, h3:hover > a.headerlink, dt:hover > a.headerlink { - visibility: visible; - } - </style><a href="index.html">Index </a>· - <a href="systemd.directives.html">Directives </a>· - <a href="../python-systemd/index.html">Python </a>· - - <span style="float:right">systemd 221</span><hr><div class="refentry"><a name="sd_journal_get_data"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>sd_journal_get_data, sd_journal_enumerate_data, sd_journal_restart_data, SD_JOURNAL_FOREACH_DATA, sd_journal_set_data_threshold, sd_journal_get_data_threshold — Read data fields from the current journal entry</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><pre class="funcsynopsisinfo">#include <systemd/sd-journal.h></pre><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_journal_get_data</b>(</code></td><td>sd_journal *<var class="pdparam">j</var>, </td></tr><tr><td> </td><td>const char *<var class="pdparam">field</var>, </td></tr><tr><td> </td><td>const void **<var class="pdparam">data</var>, </td></tr><tr><td> </td><td>size_t *<var class="pdparam">length</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_journal_enumerate_data</b>(</code></td><td>sd_journal *<var class="pdparam">j</var>, </td></tr><tr><td> </td><td>const void **<var class="pdparam">data</var>, </td></tr><tr><td> </td><td>size_t *<var class="pdparam">length</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <b class="fsfunc">sd_journal_restart_data</b>(</code></td><td>sd_journal *<var class="pdparam">j</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef"><b class="fsfunc">SD_JOURNAL_FOREACH_DATA</b>(</code></td><td>sd_journal *<var class="pdparam">j</var>, </td></tr><tr><td> </td><td>const void *<var class="pdparam">data</var>, </td></tr><tr><td> </td><td>size_t <var class="pdparam">length</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_journal_set_data_threshold</b>(</code></td><td>sd_journal *<var class="pdparam">j</var>, </td></tr><tr><td> </td><td>size_t <var class="pdparam">sz</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_journal_get_data_threshold</b>(</code></td><td>sd_journal *<var class="pdparam">j</var>, </td></tr><tr><td> </td><td>size_t *<var class="pdparam">sz</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="idm47080241744384"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p><code class="function">sd_journal_get_data()</code> 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 - <a href="systemd.journal-fields.html"><span class="citerefentry"><span class="refentrytitle">systemd.journal-fields</span>(7)</span></a>. - The returned data is in a read-only memory map and is only valid - until the next invocation of - <code class="function">sd_journal_get_data()</code> or - <code class="function">sd_journal_enumerate_data()</code>, 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 - <code class="function">sd_journal_set_data_threshold()</code> (see - below).</p><p><code class="function">sd_journal_enumerate_data()</code> 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 <code class="function">sd_journal_get_data()</code> and also - follows the same life-time semantics.</p><p><code class="function">sd_journal_restart_data()</code> resets the - data enumeration index to the beginning of the entry. The next - invocation of <code class="function">sd_journal_enumerate_data()</code> - will return the first field of the entry again.</p><p>Note that the <code class="function">SD_JOURNAL_FOREACH_DATA()</code> - macro may be used as a handy wrapper around - <code class="function">sd_journal_restart_data()</code> and - <code class="function">sd_journal_enumerate_data()</code>.</p><p>Note that these functions will not work before - <a href="sd_journal_next.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_next</span>(3)</span></a> - (or related call) has been called at least once, in order to - position the read pointer at a valid entry.</p><p><code class="function">sd_journal_set_data_threshold()</code> may be - used to change the data field size threshold for data returned by - <code class="function">sd_journal_get_data()</code>, - <code class="function">sd_journal_enumerate_data()</code> and - <code class="function">sd_journal_enumerate_unique()</code>. 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 a 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.</p><p><code class="function">sd_journal_get_data_threshold()</code> returns - the currently configured data field size threshold.</p></div><div class="refsect1"><a name="idm47080241328064"></a><h2 id="Return Value">Return Value<a class="headerlink" title="Permalink to this headline" href="#Return%20Value">¶</a></h2><p><code class="function">sd_journal_get_data()</code> 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 - <a href="sd_journal_next.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_next</span>(3)</span></a> - has not been called at least once, -EADDRNOTAVAIL is returned. - <code class="function">sd_journal_enumerate_data()</code> 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. - <code class="function">sd_journal_restart_data()</code> returns nothing. - <code class="function">sd_journal_set_data_threshold()</code> and - <code class="function">sd_journal_get_threshold()</code> return 0 on - success or a negative errno-style error code.</p></div><div class="refsect1"><a name="idm47080239790560"></a><h2 id="Notes">Notes<a class="headerlink" title="Permalink to this headline" href="#Notes">¶</a></h2><p>The <code class="function">sd_journal_get_data()</code>, - <code class="function">sd_journal_enumerate_data()</code>, - <code class="function">sd_journal_restart_data()</code>, - <code class="function">sd_journal_set_data_threshold()</code> and - <code class="function">sd_journal_get_data_threshold()</code> interfaces - are available as a shared library, which can be compiled and - linked to with the - <code class="constant">libsystemd</code> <a href="http://linux.die.net/man/1/pkg-config"><span class="citerefentry"><span class="refentrytitle">pkg-config</span>(1)</span></a> - file.</p></div><div class="refsect1"><a name="idm47080242403856"></a><h2 id="Examples">Examples<a class="headerlink" title="Permalink to this headline" href="#Examples">¶</a></h2><p>See - <a href="sd_journal_next.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_next</span>(3)</span></a> - for a complete example how to use - <code class="function">sd_journal_get_data()</code>.</p><p>Use the - <code class="function">SD_JOURNAL_FOREACH_DATA</code> macro to - iterate through all fields of the current journal - entry:</p><pre class="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); -} -...</pre></div><div class="refsect1"><a name="idm47080241920912"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p> - <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>, - <a href="systemd.journal-fields.html"><span class="citerefentry"><span class="refentrytitle">systemd.journal-fields</span>(7)</span></a>, - <a href="sd-journal.html"><span class="citerefentry"><span class="refentrytitle">sd-journal</span>(3)</span></a>, - <a href="sd_journal_open.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_open</span>(3)</span></a>, - <a href="sd_journal_next.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_next</span>(3)</span></a>, - <a href="sd_journal_get_realtime_usec.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_get_realtime_usec</span>(3)</span></a>, - <a href="sd_journal_query_unique.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_query_unique</span>(3)</span></a> - </p></div></div></body></html> |