summaryrefslogtreecommitdiff
path: root/man/sd_session_is_active.xml
blob: afdeed55d61f3d0301fb9523a3f903253158b893 (plain)
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
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
<?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 2010 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 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
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->

<refentry id="sd_session_is_active">

        <refentryinfo>
                <title>sd_session_is_active</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_session_is_active</refentrytitle>
                <manvolnum>3</manvolnum>
        </refmeta>

        <refnamediv>
                <refname>sd_session_is_active</refname>
                <refname>sd_session_get_uid</refname>
                <refname>sd_session_get_seat</refname>
                <refname>sd_session_get_service</refname>
                <refname>sd_session_get_type</refname>
                <refname>sd_session_get_class</refname>
                <refname>sd_session_get_display</refname>
                <refpurpose>Determine state of a specific session</refpurpose>
        </refnamediv>

        <refsynopsisdiv>
                <funcsynopsis>
                        <funcsynopsisinfo>#include &lt;systemd/sd-login.h&gt;</funcsynopsisinfo>

                        <funcprototype>
                                <funcdef>int <function>sd_session_is_active</function></funcdef>
                                <paramdef>const char* <parameter>session</parameter></paramdef>
                        </funcprototype>

                        <funcprototype>
                                <funcdef>int <function>sd_session_get_uid</function></funcdef>
                                <paramdef>const char* <parameter>session</parameter></paramdef>
                                <paramdef>uid_t* <parameter>uid</parameter></paramdef>
                        </funcprototype>

                        <funcprototype>
                                <funcdef>int <function>sd_session_get_seat</function></funcdef>
                                <paramdef>const char* <parameter>session</parameter></paramdef>
                                <paramdef>char** <parameter>seat</parameter></paramdef>
                        </funcprototype>

                        <funcprototype>
                                <funcdef>int <function>sd_session_get_service</function></funcdef>
                                <paramdef>const char* <parameter>session</parameter></paramdef>
                                <paramdef>char** <parameter>service</parameter></paramdef>
                        </funcprototype>

                        <funcprototype>
                                <funcdef>int <function>sd_session_get_type</function></funcdef>
                                <paramdef>const char* <parameter>session</parameter></paramdef>
                                <paramdef>char** <parameter>type</parameter></paramdef>
                        </funcprototype>

                        <funcprototype>
                                <funcdef>int <function>sd_session_get_class</function></funcdef>
                                <paramdef>const char* <parameter>session</parameter></paramdef>
                                <paramdef>char** <parameter>class</parameter></paramdef>
                        </funcprototype>

                        <funcprototype>
                                <funcdef>int <function>sd_session_get_display</function></funcdef>
                                <paramdef>const char* <parameter>session</parameter></paramdef>
                                <paramdef>char** <parameter>display</parameter></paramdef>
                        </funcprototype>
                </funcsynopsis>
        </refsynopsisdiv>

        <refsect1>
                <title>Description</title>

                <para><function>sd_session_is_active()</function> 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.</para>

                <para><function>sd_session_get_uid()</function> may be
                used to determine the user identifier of the Unix user the session
                identified by the specified session identifier belongs
                to.</para>

                <para><function>sd_session_get_seat()</function> 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
                <citerefentry><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
                call after use.</para>

                <para><function>sd_session_get_service()</function>
                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
                <citerefentry><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
                call after use.</para>

                <para><function>sd_session_get_type()</function> may
                be used to determine the type of the session
                identified by the specified session identifier. The
                returned string is one of <literal>x11</literal>,
                <literal>tty</literal> or
                <literal>unspecified</literal> and needs to be freed
                with the libc
                <citerefentry><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
                call after use.</para>

                <para><function>sd_session_get_class()</function> may
                be used to determine the class of the session
                identified by the specified session identifier. The
                returned string is one of <literal>user</literal>,
                <literal>greeter</literal> or
                <literal>lock-screen</literal> and needs to be freed
                with the libc
                <citerefentry><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
                call after use.</para>

                <para><function>sd_session_get_display()</function>
                may be used to determine the X11 display of the
                session identified by the specified session
                identifier. The returned string is one of needs to be
                freed with the libc
                <citerefentry><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
                call after use.</para>

                <para>If the <literal>session</literal> parameter of
                any of these functions is passed as NULL the operation
                is executed for the session the calling process is a
                member of, if there is any.</para>
        </refsect1>

        <refsect1>
                <title>Return Value</title>

                <para>If the test succeeds
                <function>sd_session_is_active()</function> returns a
                positive integer, if it fails 0.  On success
                <function>sd_session_get_uid()</function>,
                <function>sd_session_get_service()</function> and
                <function>sd_session_get_seat()</function> return 0 or
                a positive integer. On failure, these calls return a
                negative errno-style error code.</para>
        </refsect1>

        <refsect1>
                <title>Notes</title>

                <para>The <function>sd_session_is_active()</function>,
                <function>sd_session_get_uid()</function>,
                <function>sd_session_get_service()</function> and
                <function>sd_session_get_seat()</function> interfaces
                are available as shared library, which can be compiled
                and linked to with the
                <literal>libsystemd-login</literal>
                <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
                file.</para>
        </refsect1>

        <refsect1>
                <title>See Also</title>

                <para>
                        <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                        <citerefentry><refentrytitle>sd-login</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
                        <citerefentry><refentrytitle>sd_pid_get_session</refentrytitle><manvolnum>3</manvolnum></citerefentry>
                </para>
        </refsect1>

</refentry>