mirror of
https://github.com/systemd/systemd
synced 2024-09-06 16:56:43 +00:00
163 lines
6.4 KiB
XML
163 lines
6.4 KiB
XML
<?xml version='1.0'?> <!--*-nxml-*-->
|
|
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
|
|
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
|
|
<!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
|
|
|
|
<refentry id="sd_seat_get_active" conditional='HAVE_PAM'
|
|
xmlns:xi="http://www.w3.org/2001/XInclude">
|
|
|
|
<refentryinfo>
|
|
<title>sd_seat_get_active</title>
|
|
<productname>systemd</productname>
|
|
</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_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>ret_sessions</parameter></paramdef>
|
|
<paramdef>uid_t **<parameter>ret_uids</parameter></paramdef>
|
|
<paramdef>unsigned int *<parameter>ret_n_uids</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. This value is the same as the
|
|
return value if the return value is nonnegative. The output parameters may be passed as
|
|
<constant>NULL</constant> in case these output values are not needed. 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_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_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>
|
|
|
|
<refsect2>
|
|
<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 <constant>NULL</constant>, where
|
|
that is not accepted).</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>-ENOMEM</constant></term>
|
|
|
|
<listitem><para>Memory allocation failed.</para></listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</refsect2>
|
|
</refsect1>
|
|
|
|
<xi:include href="libsystemd-pkgconfig.xml" />
|
|
|
|
<refsect1>
|
|
<title>History</title>
|
|
|
|
<para>In the past, <function>sd_seat_can_multi_session()</function> was used to check whether the seat
|
|
supports multiple sessions. All seats support that now, so that function has been deprecated and always
|
|
returns true.</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>
|