1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
|
<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>sd_seat_get_active</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_seat_get_active"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>sd_seat_get_active, sd_seat_get_sessions, sd_seat_can_multi_session, sd_seat_can_tty, sd_seat_can_graphical — Determine state of a specific seat</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><pre class="funcsynopsisinfo">#include <systemd/sd-login.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_seat_get_active</b>(</code></td><td>const char *<var class="pdparam">seat</var>, </td></tr><tr><td> </td><td>char **<var class="pdparam">session</var>, </td></tr><tr><td> </td><td>uid_t *<var class="pdparam">uid</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_seat_get_sessions</b>(</code></td><td>const char *<var class="pdparam">seat</var>, </td></tr><tr><td> </td><td>char ***<var class="pdparam">sessions</var>, </td></tr><tr><td> </td><td>uid_t **<var class="pdparam">uid</var>, </td></tr><tr><td> </td><td>unsigned int *<var class="pdparam">n_uids</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_seat_can_multi_session</b>(</code></td><td>const char *<var class="pdparam">seat</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_seat_can_tty</b>(</code></td><td>const char *<var class="pdparam">seat</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_seat_can_graphical</b>(</code></td><td>const char *<var class="pdparam">seat</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="idm47864436384000"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p><code class="function">sd_seat_get_active()</code> may be used to
determine which session is currently active on a seat, if there is
any. Returns the session identifier and the user identifier of the
Unix user the session is belonging to. Either the session or the
user identifier parameter can be passed <code class="constant">NULL</code>,
in case only one of the parameters shall be queried. The returned
string needs to be freed with the libc
<a href="http://man7.org/linux/man-pages/man3/free.3.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
call after use.</p><p><code class="function">sd_seat_get_sessions()</code> may be used to
determine all sessions on the specified seat. Returns two arrays,
one (<code class="constant">NULL</code> terminated) with the session
identifiers of the sessions and one with the user identifiers of
the Unix users the sessions belong to. An additional parameter may
be used to return the number of entries in the latter array. The
two arrays and the latter parameter may be passed as
<code class="constant">NULL</code> in case these values need not to be
determined. The arrays and the strings referenced by them need to
be freed with the libc
<a href="http://man7.org/linux/man-pages/man3/free.3.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
call after use. Note that instead of an empty array
<code class="constant">NULL</code> may be returned and should be considered
equivalent to an empty array.</p><p><code class="function">sd_seat_can_multi_session()</code> may be used
to determine whether a specific seat is capable of multi-session,
i.e. allows multiple login sessions in parallel (with only one
being active at a time).</p><p><code class="function">sd_seat_can_tty()</code> may be used to
determine whether a specific seat provides TTY functionality, i.e.
is useful as a text console.</p><p><code class="function">sd_seat_can_graphical()</code> may be used to
determine whether a specific seat provides graphics functionality,
i.e. is useful as a graphics display.</p><p>If the <code class="varname">seat</code> parameter of any of these
functions is passed as <code class="constant">NULL</code>, the operation is
executed for the seat of the session of the calling process, if
there is any.</p></div><div class="refsect1"><a name="idm47864436372528"></a><h2 id="Return Value">Return Value<a class="headerlink" title="Permalink to this headline" href="#Return%20Value">¶</a></h2><p> On success, <code class="function">sd_seat_get_active()</code>
returns 0 or a positive integer. On success,
<code class="function">sd_seat_get_sessions()</code> returns the number of
entries in the session identifier array. If the test succeeds,
<code class="function">sd_seat_can_multi_session</code>,
<code class="function">sd_seat_can_tty</code> and
<code class="function">sd_seat_can_graphical</code> return a positive
integer, if it fails 0. On failure, these calls return a negative
errno-style error code.</p></div><div class="refsect1"><a name="idm47864436368016"></a><h2 id="Notes">Notes<a class="headerlink" title="Permalink to this headline" href="#Notes">¶</a></h2><p>The <code class="function">sd_seat_get_active()</code>,
<code class="function">sd_seat_get_sessions()</code>,
<code class="function">sd_seat_can_multi_session()</code>,
<code class="function">sd_seat_can_tty()</code> and
<code class="function">sd_seat_can_grapical()</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="idm47864436362224"></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="sd-login.html"><span class="citerefentry"><span class="refentrytitle">sd-login</span>(3)</span></a>,
<a href="sd_session_get_seat.html"><span class="citerefentry"><span class="refentrytitle">sd_session_get_seat</span>(3)</span></a>
</p></div></div></body></html>
|
