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  </style><a href="index.html">Index </a>·
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  <a href="../libudev/index.html">gudev </a><span style="float:right">systemd 214</span><hr><div class="refentry"><a name="sd_session_is_active"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>sd_session_is_active, sd_session_is_remote, sd_session_get_state, sd_session_get_uid, sd_session_get_seat, sd_session_get_service, sd_session_get_type, sd_session_get_class, sd_session_get_display, sd_session_get_tty, sd_session_get_vt, sd_session_get_remote_host, sd_session_get_remote_user — Determine state of a specific session</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><pre class="funcsynopsisinfo">#include &lt;systemd/sd-login.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_session_is_active</b>(</code></td><td>const char *<var class="pdparam">session</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_session_is_remote</b>(</code></td><td>const char *<var class="pdparam">session</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_session_get_state</b>(</code></td><td>const char *<var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char **<var class="pdparam">state</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_session_get_uid</b>(</code></td><td>const 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_session_get_seat</b>(</code></td><td>const char *<var class="pdparam">session</var>, </td></tr><tr><td> </td><td>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_session_get_service</b>(</code></td><td>const char *<var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char **<var class="pdparam">service</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_session_get_type</b>(</code></td><td>const char *<var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char **<var class="pdparam">type</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_session_get_class</b>(</code></td><td>const char *<var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char **<var class="pdparam">class</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_session_get_display</b>(</code></td><td>const char *<var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char **<var class="pdparam">display</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_session_get_remote_host</b>(</code></td><td>const char *<var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char **<var class="pdparam">remote_host</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_session_get_remote_user</b>(</code></td><td>const char *<var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char **<var class="pdparam">remote_user</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_session_get_tty</b>(</code></td><td>const char *<var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char **<var class="pdparam">tty</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_session_get_vt</b>(</code></td><td>const char *<var class="pdparam">session</var>, </td></tr><tr><td> </td><td>unsigned int *<var class="pdparam">vt</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="idm214187472368"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p><code class="function">sd_session_is_active()</code> may
                be used to determine whether the session identified by
                the specified session identifier is currently active
                (i.e. currently in the foreground and available for
                user input) or not.</p><p><code class="function">sd_session_is_remote()</code> may
                be used to determine whether the session identified by
                the specified session identifier is a remote session
                (i.e. its remote host is known) or not.</p><p><code class="function">sd_session_get_state()</code> may
                be used to determine the state of the session
                identified by the specified session identifier. The
                following states are currently known:
                "<code class="literal">online</code>" (session logged in, but
                session not active, i.e. not in the foreground),
                "<code class="literal">active</code>" (session logged in and
                active, i.e. in the foreground),
                "<code class="literal">closing</code>" (session nominally logged
                out, but some processes belonging to it are still
                around). In the future additional states might be
                defined, client code should be written to be robust in
                regards to additional state strings being
                returned. This function is a more generic version of
                <code class="function">sd_session_is_active()</code>. The returned
                string needs to be freed with the libc
                <a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
                call after use.</p><p><code class="function">sd_session_get_uid()</code> may be
                used to determine the user identifier of the Unix user the session
                identified by the specified session identifier belongs
                to.</p><p><code class="function">sd_session_get_seat()</code> may
                be used to determine the seat identifier of the seat
                the session identified by the specified session
                identifier belongs to. Note that not all sessions are
                attached to a seat, this call will fail for them. The
                returned string needs to be freed with the libc
                <a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
                call after use.</p><p><code class="function">sd_session_get_service()</code>
                may be used to determine the name of the service (as
                passed during PAM session setup) that registered the
                session identified by the specified session
                identifier. The returned string needs to be freed with
                the libc
                <a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
                call after use.</p><p><code class="function">sd_session_get_type()</code> may
                be used to determine the type of the session
                identified by the specified session identifier. The
                returned string is one of "<code class="literal">x11</code>",
                "<code class="literal">wayland</code>", "<code class="literal">tty</code>",
                "<code class="literal">mir</code>" or "<code class="literal">unspecified</code>" and
                needs to be freed with the libc
                <a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
                call after use.</p><p><code class="function">sd_session_get_class()</code> may
                be used to determine the class of the session
                identified by the specified session identifier. The
                returned string is one of "<code class="literal">user</code>",
                "<code class="literal">greeter</code>",
                "<code class="literal">lock-screen</code>", or
                "<code class="literal">background</code>" and needs to be freed
                with the libc
                <a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
                call after use.</p><p><code class="function">sd_session_get_display()</code>
                may be used to determine the X11 display of the
                session identified by the specified session
                identifier. The returned string needs to be
                freed with the libc
                <a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
                call after use.</p><p><code class="function">sd_session_get_remote_host()</code>
                may be used to determine the remote hostname of the
                session identified by the specified session
                identifier. The returned string needs to be
                freed with the libc
                <a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
                call after use.</p><p><code class="function">sd_session_get_remote_user()</code>
                may be used to determine the remote username of the
                session identified by the specified session
                identifier. The returned string needs to be
                freed with the libc
                <a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
                call after use. Note that this value is rarely known
                to the system, and even then should not be relied on.</p><p><code class="function">sd_session_get_tty()</code>
                may be used to determine the TTY device of the
                session identified by the specified session
                identifier. The returned string needs to be
                freed with the libc
                <a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
                call after use.</p><p><code class="function">sd_session_get_vt()</code>
                may be used to determine the VT number of the
                session identified by the specified session
                identifier. This function will return an error if
                the seat does not support VTs.</p><p>If the <code class="varname">session</code> parameter of
                any of these functions is passed as
                <code class="constant">NULL</code>, the operation is executed
                for the session the calling process is a member of, if
                there is any.</p></div><div class="refsect1"><a name="idm214182525232"></a><h2 id="Return Value">Return Value<a class="headerlink" title="Permalink to this headline" href="#Return%20Value">¶</a></h2><p>If the test succeeds,
                <code class="function">sd_session_is_active()</code> and
                <code class="function">sd_session_is_remote()</code> return a
                positive integer; if it fails, 0.  On success,
                <code class="function">sd_session_get_state()</code>,
                <code class="function">sd_session_get_uid()</code>,
                <code class="function">sd_session_get_seat()</code>,
                <code class="function">sd_session_get_service()</code>,
                <code class="function">sd_session_get_type()</code>,
                <code class="function">sd_session_get_class()</code>,
                <code class="function">sd_session_get_display()</code>,
                <code class="function">sd_session_get_remote_user()</code>,
                <code class="function">sd_session_get_remote_host()</code> and
                <code class="function">sd_session_get_tty()</code> return 0 or
                a positive integer. On failure, these calls return a
                negative errno-style error code.</p></div><div class="refsect1"><a name="idm214182516336"></a><h2 id="Notes">Notes<a class="headerlink" title="Permalink to this headline" href="#Notes">¶</a></h2><p>The <code class="function">sd_session_is_active()</code>,
                <code class="function">sd_session_get_state()</code>,
                <code class="function">sd_session_get_uid()</code>,
                <code class="function">sd_session_get_seat()</code>,
                <code class="function">sd_session_get_service()</code>,
                <code class="function">sd_session_get_type()</code>,
                <code class="function">sd_session_get_class()</code>,
                <code class="function">sd_session_get_display()</code>,
                <code class="function">sd_session_get_remote_host()</code>,
                <code class="function">sd_session_get_remote_user()</code> and
                <code class="function">sd_session_get_tty()</code>
                interfaces are available as a shared library, which can
                be compiled and linked to with the
                <code class="constant">libsystemd</code> <a href="pkg-config.html"><span class="citerefentry"><span class="refentrytitle">pkg-config</span>(1)</span></a>
                file.</p></div><div class="refsect1"><a name="idm214182507008"></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_pid_get_session.html"><span class="citerefentry"><span class="refentrytitle">sd_pid_get_session</span>(3)</span></a>
                </p></div></div></body></html>
Commit	Line	Data
663996b3 MS	1	<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>sd_session_is_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>
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60f067b4	22	<a href="../libudev/index.html">gudev </a><span style="float:right">systemd 214</span><hr><div class="refentry"><a name="sd_session_is_active"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>sd_session_is_active, sd_session_is_remote, sd_session_get_state, sd_session_get_uid, sd_session_get_seat, sd_session_get_service, sd_session_get_type, sd_session_get_class, sd_session_get_display, sd_session_get_tty, sd_session_get_vt, sd_session_get_remote_host, sd_session_get_remote_user — Determine state of a specific session</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_session_is_active</b>(</code></td><td>const char <var class="pdparam">session</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_session_is_remote</b>(</code></td><td>const char <var class="pdparam">session</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_session_get_state</b>(</code></td><td>const char <var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char <var class="pdparam">state</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_session_get_uid</b>(</code></td><td>const 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_session_get_seat</b>(</code></td><td>const char <var class="pdparam">session</var>, </td></tr><tr><td> </td><td>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_session_get_service</b>(</code></td><td>const char <var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char *<var class="pdparam">service</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_session_get_type</b>(</code></td><td>const char <var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char *<var class="pdparam">type</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_session_get_class</b>(</code></td><td>const char <var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char *<var class="pdparam">class</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_session_get_display</b>(</code></td><td>const char <var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char *<var class="pdparam">display</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_session_get_remote_host</b>(</code></td><td>const char <var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char *<var class="pdparam">remote_host</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_session_get_remote_user</b>(</code></td><td>const char <var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char *<var class="pdparam">remote_user</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_session_get_tty</b>(</code></td><td>const char <var class="pdparam">session</var>, </td></tr><tr><td> </td><td>char *<var class="pdparam">tty</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_session_get_vt</b>(</code></td><td>const char <var class="pdparam">session</var>, </td></tr><tr><td> </td><td>unsigned int *<var class="pdparam">vt</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="idm214187472368"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p><code class="function">sd_session_is_active()</code> may
663996b3 MS	23	be used to determine whether the session identified by
	24	the specified session identifier is currently active
	25	(i.e. currently in the foreground and available for
60f067b4 JS	26	user input) or not.</p><p><code class="function">sd_session_is_remote()</code> may
	27	be used to determine whether the session identified by
	28	the specified session identifier is a remote session
	29	(i.e. its remote host is known) or not.</p><p><code class="function">sd_session_get_state()</code> may
663996b3 MS	30	be used to determine the state of the session
	31	identified by the specified session identifier. The
	32	following states are currently known:
14228c0d	33	"<code class="literal">online</code>" (session logged in, but
663996b3	34	session not active, i.e. not in the foreground),
14228c0d	35	"<code class="literal">active</code>" (session logged in and
663996b3	36	active, i.e. in the foreground),
14228c0d	37	"<code class="literal">closing</code>" (session nominally logged
663996b3 MS	38	out, but some processes belonging to it are still
	39	around). In the future additional states might be
	40	defined, client code should be written to be robust in
	41	regards to additional state strings being
	42	returned. This function is a more generic version of
	43	<code class="function">sd_session_is_active()</code>. The returned
	44	string needs to be freed with the libc
	45	<a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
	46	call after use.</p><p><code class="function">sd_session_get_uid()</code> may be
	47	used to determine the user identifier of the Unix user the session
	48	identified by the specified session identifier belongs
	49	to.</p><p><code class="function">sd_session_get_seat()</code> may
	50	be used to determine the seat identifier of the seat
	51	the session identified by the specified session
	52	identifier belongs to. Note that not all sessions are
	53	attached to a seat, this call will fail for them. The
	54	returned string needs to be freed with the libc
	55	<a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
	56	call after use.</p><p><code class="function">sd_session_get_service()</code>
	57	may be used to determine the name of the service (as
	58	passed during PAM session setup) that registered the
	59	session identified by the specified session
	60	identifier. The returned string needs to be freed with
	61	the libc
	62	<a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
	63	call after use.</p><p><code class="function">sd_session_get_type()</code> may
	64	be used to determine the type of the session
	65	identified by the specified session identifier. The
14228c0d	66	returned string is one of "<code class="literal">x11</code>",
60f067b4 JS	67	"<code class="literal">wayland</code>", "<code class="literal">tty</code>",
	68	"<code class="literal">mir</code>" or "<code class="literal">unspecified</code>" and
	69	needs to be freed with the libc
663996b3 MS	70	<a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
	71	call after use.</p><p><code class="function">sd_session_get_class()</code> may
	72	be used to determine the class of the session
	73	identified by the specified session identifier. The
14228c0d MB	74	returned string is one of "<code class="literal">user</code>",
	75	"<code class="literal">greeter</code>",
	76	"<code class="literal">lock-screen</code>", or
	77	"<code class="literal">background</code>" and needs to be freed
663996b3 MS	78	with the libc
	79	<a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
	80	call after use.</p><p><code class="function">sd_session_get_display()</code>
	81	may be used to determine the X11 display of the
	82	session identified by the specified session
	83	identifier. The returned string needs to be
	84	freed with the libc
	85	<a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
60f067b4 JS	86	call after use.</p><p><code class="function">sd_session_get_remote_host()</code>
	87	may be used to determine the remote hostname of the
	88	session identified by the specified session
	89	identifier. The returned string needs to be
	90	freed with the libc
	91	<a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
	92	call after use.</p><p><code class="function">sd_session_get_remote_user()</code>
	93	may be used to determine the remote username of the
	94	session identified by the specified session
	95	identifier. The returned string needs to be
	96	freed with the libc
	97	<a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
	98	call after use. Note that this value is rarely known
	99	to the system, and even then should not be relied on.</p><p><code class="function">sd_session_get_tty()</code>
663996b3 MS	100	may be used to determine the TTY device of the
	101	session identified by the specified session
	102	identifier. The returned string needs to be
	103	freed with the libc
	104	<a href="free.html"><span class="citerefentry"><span class="refentrytitle">free</span>(3)</span></a>
14228c0d MB	105	call after use.</p><p><code class="function">sd_session_get_vt()</code>
	106	may be used to determine the VT number of the
	107	session identified by the specified session
	108	identifier. This function will return an error if
	109	the seat does not support VTs.</p><p>If the <code class="varname">session</code> parameter of
	110	any of these functions is passed as
	111	<code class="constant">NULL</code>, the operation is executed
	112	for the session the calling process is a member of, if
60f067b4 JS	113	there is any.</p></div><div class="refsect1"><a name="idm214182525232"></a><h2 id="Return Value">Return Value<a class="headerlink" title="Permalink to this headline" href="#Return%20Value">¶</a></h2><p>If the test succeeds,
	114	<code class="function">sd_session_is_active()</code> and
	115	<code class="function">sd_session_is_remote()</code> return a
	116	positive integer; if it fails, 0. On success,
663996b3 MS	117	<code class="function">sd_session_get_state()</code>,
	118	<code class="function">sd_session_get_uid()</code>,
	119	<code class="function">sd_session_get_seat()</code>,
	120	<code class="function">sd_session_get_service()</code>,
	121	<code class="function">sd_session_get_type()</code>,
	122	<code class="function">sd_session_get_class()</code>,
60f067b4 JS	123	<code class="function">sd_session_get_display()</code>,
	124	<code class="function">sd_session_get_remote_user()</code>,
	125	<code class="function">sd_session_get_remote_host()</code> and
663996b3 MS	126	<code class="function">sd_session_get_tty()</code> return 0 or
663996b3 MS	127	a positive integer. On failure, these calls return a
60f067b4	128	negative errno-style error code.</p></div><div class="refsect1"><a name="idm214182516336"></a><h2 id="Notes">Notes<a class="headerlink" title="Permalink to this headline" href="#Notes">¶</a></h2><p>The <code class="function">sd_session_is_active()</code>,
663996b3 MS	129	<code class="function">sd_session_get_state()</code>,
	130	<code class="function">sd_session_get_uid()</code>,
	131	<code class="function">sd_session_get_seat()</code>,
	132	<code class="function">sd_session_get_service()</code>,
	133	<code class="function">sd_session_get_type()</code>,
	134	<code class="function">sd_session_get_class()</code>,
60f067b4 JS	135	<code class="function">sd_session_get_display()</code>,
	136	<code class="function">sd_session_get_remote_host()</code>,
	137	<code class="function">sd_session_get_remote_user()</code> and
663996b3	138	<code class="function">sd_session_get_tty()</code>
60f067b4	139	interfaces are available as a shared library, which can
663996b3	140	be compiled and linked to with the
60f067b4 JS	141	<code class="constant">libsystemd</code> <a href="pkg-config.html"><span class="citerefentry"><span class="refentrytitle">pkg-config</span>(1)</span></a>
60f067b4 JS	142	file.</p></div><div class="refsect1"><a name="idm214182507008"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p>
663996b3 MS	143	<a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>,
	144	<a href="sd-login.html"><span class="citerefentry"><span class="refentrytitle">sd-login</span>(3)</span></a>,
	145	<a href="sd_pid_get_session.html"><span class="citerefentry"><span class="refentrytitle">sd_pid_get_session</span>(3)</span></a>
	146	</p></div></div></body></html>