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  • Committer: Package Import Robot
  • Author(s): Michael Biebl, Michael Biebl, Michael Stapelberg, Daniel Schaal, Ondrej Balaz
  • Date: 2013-09-12 00:13:11 UTC
  • mfrom: (1.1.11) (9.1.2 experimental)
  • mto: This revision was merged to the branch mainline in revision 53.
  • Revision ID: package-import@ubuntu.com-20130912001311-dz35it34wr2lbday
Tags: 204-3
http://bugs.debian.org/719444
http://bugs.debian.org/721347
http://bugs.debian.org/722180
http://bugs.debian.org/709780
http://bugs.debian.org/711245
[ Michael Biebl ]
* Upload to unstable.
* Use /bin/bash in debug-shell.service as Debian doesn't have /sbin/sushell.
* Only import net.ifaces cmdline property for network devices.
* Generate strict dependencies between the binary packages using a
  shlibs.local file and add an explicit versioned dependency on
  libsystemd-login0 to systemd to ensure packages are upgraded in sync.
  Closes: #719444
* Drop obsolete Replaces: libudev0 from udev package.
* Use correct paths for various binaries, like /sbin/quotaon, which are
  installed in / and not /usr in Debian.  Closes: #721347
* Don't install kernel-install(8) man page since we don't install the
  corresponding binary either.  Closes: #722180
* Cherry-pick upstream fixes to make switching runlevels and starting
  reboot via ctrl-alt-del more robust.
* Cherry-pick upstream fix to properly apply ACLs to Journal files.

[ Michael Stapelberg ]
* Make systemctl enable|disable call update-rc.d for SysV init scripts.
  Closes: #709780
* Don't mount /tmp as tmpfs by default and make it possible to enable this
  feature via "systemctl enable tmp.mount".

[ Daniel Schaal ]
* Add bug-script to systemd and udev.  Closes: #711245

[ Ondrej Balaz ]
* Recognize discard option in /etc/crypttab.

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man/sd_journal_enumerate_data.html
 
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<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>
 
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  </style><a href="index.html">Index </a>·
 
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  <a href="systemd.directives.html">Directives </a>·
 
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  <a href="../python-systemd/index.html">Python </a>·
 
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  <a href="../libudev/index.html">libudev </a>·
 
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  <a href="../libudev/index.html">gudev </a><span style="float:right">systemd 204</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 &lt;systemd/sd-journal.h&gt;</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="idm259782712960"></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
 
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                the data object associated with a specific field from
 
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                the current journal entry. It takes four arguments:
 
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                the journal context object, a string with the field
 
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                name to request, plus a pair of pointers to
 
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                pointer/size variables where the data object and its
 
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                size shall be stored in. The field name should be an
 
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                entry field name. Well-known field names are listed in
 
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                <a href="systemd.journal-fields.html"><span class="citerefentry"><span class="refentrytitle">systemd.journal-fields</span>(7)</span></a>. The
 
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                returned data is in a read-only memory map and is only
 
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                valid until the next invocation of
 
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                <code class="function">sd_journal_get_data()</code> or
 
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                <code class="function">sd_journal_enumerate_data()</code>, or
 
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                the read pointer is altered. Note that the data
 
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                returned will be prefixed with the field name and
 
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                '='. Also note that by default data fields larger than
 
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                64K might get truncated to 64K. This threshold may be
 
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                changed and turned off with
 
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                <code class="function">sd_journal_set_data_threshold()</code> (see
 
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                below).</p><p><code class="function">sd_journal_enumerate_data()</code>
 
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                may be used to iterate through all fields of the
 
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                current entry. On each invocation the data for the
 
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                next field is returned. The order of these fields is
 
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                not defined. The data returned is in the same format
 
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                as with <code class="function">sd_journal_get_data()</code> and
 
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                also follows the same life-time semantics.</p><p><code class="function">sd_journal_restart_data()</code>
 
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                resets the data enumeration index to the beginning of
 
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                the entry. The next invocation of
 
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                <code class="function">sd_journal_enumerate_data()</code> will return the first
 
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                field of the entry again.</p><p>Note that the
 
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                <code class="function">SD_JOURNAL_FOREACH_DATA()</code> macro
 
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                may be used as a handy wrapper around
 
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                <code class="function">sd_journal_restart_data()</code> and
 
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                <code class="function">sd_journal_enumerate_data()</code>.</p><p>Note that these functions will not work before
 
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                <a href="sd_journal_next.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_next</span>(3)</span></a>
 
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                (or related call) has been called at least
 
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                once, in order to position the read pointer at a valid entry.</p><p><code class="function">sd_journal_set_data_threshold()</code>
 
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                may be used to change the data field size threshold
 
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                for data returned by
 
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                <code class="function">sd_journal_get_data()</code>,
 
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                <code class="function">sd_journal_enumerate_data()</code> and
 
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                <code class="function">sd_journal_enumerate_unique()</code>. This
 
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                threshold is a hint only: it indicates that the client
 
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                program is interested only in the initial parts of the
 
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                data fields, up to the threshold in size -- but the
 
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                library might still return larger data objects. That
 
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                means applications should not rely exclusively on this
 
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                setting to limit the size of the data fields returned,
 
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                but need to apply a explicit size limit on the
 
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                returned data as well. This threshold defaults to 64K
 
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                by default. To retrieve the complete data fields this
 
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                threshold should be turned off by setting it to 0, so
 
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                that the library always returns the complete data
 
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                objects. It is recommended to set this threshold as
 
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                low as possible since this relieves the library from
 
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                having to decompress large compressed data objects in
 
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                full.</p><p><code class="function">sd_journal_get_data_threshold()</code>
 
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                returns the currently configured data field size
 
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                threshold.</p></div><div class="refsect1"><a name="idm259782687296"></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>
 
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                returns 0 on success or a negative errno-style error
 
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                code. If the current entry does not include the
 
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                specified field -ENOENT is returned. If
 
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                <a href="sd_journal_next.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_next</span>(3)</span></a>
 
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                has not been called at least once -EADDRNOTAVAIL is
 
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                returned. <code class="function">sd_journal_enumerate_data()</code>
 
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                returns a positive integer if the next field has been
 
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                read, 0 when no more fields are known, or a negative
 
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                errno-style error
 
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                code. <code class="function">sd_journal_restart_data()</code>
 
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                returns
 
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                nothing. <code class="function">sd_journal_set_data_threshold()</code>
 
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                and <code class="function">sd_journal_get_threshold()</code>
 
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                return 0 on success or a negative errno-style error
 
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                code.</p></div><div class="refsect1"><a name="idm259782681248"></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>,
 
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                <code class="function">sd_journal_enumerate_data()</code>,
 
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                <code class="function">sd_journal_restart_data()</code>,
 
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                <code class="function">sd_journal_set_data_threshold()</code>
 
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                and
 
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                <code class="function">sd_journal_get_data_threshold()</code>
 
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                interfaces are available as shared library, which can
 
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                be compiled and linked to with the
 
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                <code class="literal">libsystemd-journal</code>
 
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                <a href="pkg-config.html"><span class="citerefentry"><span class="refentrytitle">pkg-config</span>(1)</span></a>
 
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                file.</p></div><div class="refsect1"><a name="idm259777759888"></a><h2 id="Examples">Examples<a class="headerlink" title="Permalink to this headline" href="#Examples">¶</a></h2><p>See
 
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                <a href="sd_journal_next.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_next</span>(3)</span></a>
 
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                for a complete example how to use
 
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                <code class="function">sd_journal_get_data()</code>.</p><p>Use the
 
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                <code class="function">SD_JOURNAL_FOREACH_DATA</code> macro to
 
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                iterate through all fields of the current journal
 
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                entry:</p><pre class="programlisting">...
 
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int print_fields(sd_journal *j) {
 
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        const void *data;
 
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        size_t l;
 
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        SD_JOURNAL_FOREACH_DATA(j, data, length)
 
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                printf("%.*s\n", (int) length, data);
 
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}
 
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...</pre></div><div class="refsect1"><a name="idm259777755392"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p>
 
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                        <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>,
 
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                        <a href="systemd.journal-fields.html"><span class="citerefentry"><span class="refentrytitle">systemd.journal-fields</span>(7)</span></a>,
 
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                        <a href="sd-journal.html"><span class="citerefentry"><span class="refentrytitle">sd-journal</span>(3)</span></a>,
 
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                        <a href="sd_journal_open.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_open</span>(3)</span></a>,
 
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                        <a href="sd_journal_next.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_next</span>(3)</span></a>,
 
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                        <a href="sd_journal_get_realtime_usec.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_get_realtime_usec</span>(3)</span></a>,
 
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                        <a href="sd_journal_query_unique.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_query_unique</span>(3)</span></a>
 
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                </p></div></div></body></html>