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
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
|
<?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 Lesser General Public License as published by
the Free Software Foundation; either version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser 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_state</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 <systemd/sd-login.h></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_state</function></funcdef>
<paramdef>const char* <parameter>session</parameter></paramdef>
<paramdef>char** <parameter>state</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_state()</function> may
be used to determine the state of the session
identified by the specified session identifier. The
following states are currently known:
<literal>online</literal> (session logged in, but
session not active, i.e. not in the foreground),
<literal>active</literal> (session logged in and
active, i.e. in the foreground),
<literal>closing</literal> (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
<function>sd_session_is_active()</function>. 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_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>
|
