213 lines
7.9 KiB
XML
213 lines
7.9 KiB
XML
<?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_seat_get_active" conditional='HAVE_PAM'>
|
||
|
||
<refentryinfo>
|
||
<title>sd_seat_get_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_seat_get_active</refentrytitle>
|
||
<manvolnum>3</manvolnum>
|
||
</refmeta>
|
||
|
||
<refnamediv>
|
||
<refname>sd_seat_get_active</refname>
|
||
<refname>sd_seat_get_sessions</refname>
|
||
<refname>sd_seat_can_multi_session</refname>
|
||
<refname>sd_seat_can_tty</refname>
|
||
<refname>sd_seat_can_graphical</refname>
|
||
<refpurpose>Determine state of a specific seat</refpurpose>
|
||
</refnamediv>
|
||
|
||
<refsynopsisdiv>
|
||
<funcsynopsis>
|
||
<funcsynopsisinfo>#include <systemd/sd-login.h></funcsynopsisinfo>
|
||
|
||
<funcprototype>
|
||
<funcdef>int <function>sd_seat_get_active</function></funcdef>
|
||
<paramdef>const char *<parameter>seat</parameter></paramdef>
|
||
<paramdef>char **<parameter>session</parameter></paramdef>
|
||
<paramdef>uid_t *<parameter>uid</parameter></paramdef>
|
||
</funcprototype>
|
||
|
||
<funcprototype>
|
||
<funcdef>int <function>sd_seat_get_sessions</function></funcdef>
|
||
<paramdef>const char *<parameter>seat</parameter></paramdef>
|
||
<paramdef>char ***<parameter>sessions</parameter></paramdef>
|
||
<paramdef>uid_t **<parameter>uid</parameter></paramdef>
|
||
<paramdef>unsigned int *<parameter>n_uids</parameter></paramdef>
|
||
</funcprototype>
|
||
|
||
<funcprototype>
|
||
<funcdef>int <function>sd_seat_can_multi_session</function></funcdef>
|
||
<paramdef>const char *<parameter>seat</parameter></paramdef>
|
||
</funcprototype>
|
||
|
||
<funcprototype>
|
||
<funcdef>int <function>sd_seat_can_tty</function></funcdef>
|
||
<paramdef>const char *<parameter>seat</parameter></paramdef>
|
||
</funcprototype>
|
||
|
||
<funcprototype>
|
||
<funcdef>int <function>sd_seat_can_graphical</function></funcdef>
|
||
<paramdef>const char *<parameter>seat</parameter></paramdef>
|
||
</funcprototype>
|
||
</funcsynopsis>
|
||
</refsynopsisdiv>
|
||
|
||
<refsect1>
|
||
<title>Description</title>
|
||
|
||
<para><function>sd_seat_get_active()</function> 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 <constant>NULL</constant>,
|
||
in case only one of the parameters shall be queried. The returned
|
||
string needs to be freed with the libc
|
||
<citerefentry project='man-pages'><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
||
call after use.</para>
|
||
|
||
<para><function>sd_seat_get_sessions()</function> may be used to
|
||
determine all sessions on the specified seat. Returns two arrays,
|
||
one (<constant>NULL</constant> 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
|
||
<constant>NULL</constant> in case these values need not to be
|
||
determined. The arrays and the strings referenced by them need to
|
||
be freed with the libc
|
||
<citerefentry project='man-pages'><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
||
call after use. Note that instead of an empty array
|
||
<constant>NULL</constant> may be returned and should be considered
|
||
equivalent to an empty array.</para>
|
||
|
||
<para><function>sd_seat_can_multi_session()</function> 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).</para>
|
||
|
||
<para><function>sd_seat_can_tty()</function> may be used to
|
||
determine whether a specific seat provides TTY functionality, i.e.
|
||
is useful as a text console.</para>
|
||
|
||
<para><function>sd_seat_can_graphical()</function> may be used to
|
||
determine whether a specific seat provides graphics functionality,
|
||
i.e. is useful as a graphics display.</para>
|
||
|
||
<para>If the <varname>seat</varname> parameter of any of these
|
||
functions is passed as <constant>NULL</constant>, the operation is
|
||
executed for the seat of the session of the calling process, if
|
||
there is any.</para>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>Return Value</title>
|
||
|
||
<para> On success, <function>sd_seat_get_active()</function>
|
||
returns 0 or a positive integer. On success,
|
||
<function>sd_seat_get_sessions()</function> returns the number of
|
||
entries in the session identifier array. If the test succeeds,
|
||
<function>sd_seat_can_multi_session</function>,
|
||
<function>sd_seat_can_tty</function> and
|
||
<function>sd_seat_can_graphical</function> return a positive
|
||
integer, if it fails 0. On failure, these calls return a negative
|
||
errno-style error code.</para>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>Errors</title>
|
||
|
||
<para>Returned errors may indicate the following problems:</para>
|
||
|
||
<variablelist>
|
||
|
||
<varlistentry>
|
||
<term><constant>-ENODATA</constant></term>
|
||
|
||
<listitem><para>The given field is not specified for the described
|
||
seat.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><constant>-ENXIO</constant></term>
|
||
|
||
<listitem><para>The specified seat is unknown.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><constant>-EINVAL</constant></term>
|
||
|
||
<listitem><para>An input parameter was invalid (out of range,
|
||
or NULL, where that's not accepted).</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><constant>-ENOMEM</constant></term>
|
||
|
||
<listitem><para>Memory allocation failed.</para></listitem>
|
||
</varlistentry>
|
||
</variablelist>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>Notes</title>
|
||
|
||
<para>The <function>sd_seat_get_active()</function>,
|
||
<function>sd_seat_get_sessions()</function>,
|
||
<function>sd_seat_can_multi_session()</function>,
|
||
<function>sd_seat_can_tty()</function> and
|
||
<function>sd_seat_can_grapical()</function> interfaces are
|
||
available as a shared library, which can be compiled and linked to
|
||
with the
|
||
<constant>libsystemd</constant> <citerefentry project='die-net'><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>3</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>sd_session_get_seat</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
||
</para>
|
||
</refsect1>
|
||
|
||
</refentry>
|