--- /dev/null
+<?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="pam_elogind" conditional='HAVE_PAM'>
+
+ <refentryinfo>
+ <title>pam_elogind</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>pam_elogind</refentrytitle>
+ <manvolnum>8</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>pam_elogind</refname>
+ <refpurpose>Register user sessions in the elogind login manager</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <para><filename>pam_elogind.so</filename></para>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><command>pam_elogind</command> registers user sessions with
+ the elogind login manager
+ <citerefentry><refentrytitle>logind</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ and hence the elogind control group hierarchy.</para>
+
+ <para>On login, this module ensures the following:</para>
+
+ <orderedlist>
+ <listitem><para>If it does not exist yet, the user runtime
+ directory <filename>/run/user/$USER</filename> is created and
+ its ownership changed to the user that is logging
+ in.</para></listitem>
+
+ <listitem><para>The <varname>$XDG_SESSION_ID</varname>
+ environment variable is initialized. If auditing is available
+ and <command>pam_loginuid.so</command> was run before this
+ module (which is highly recommended), the variable is
+ initialized from the auditing session id
+ (<filename>/proc/self/sessionid</filename>). Otherwise, an
+ independent session counter is used.</para></listitem>
+
+ <listitem><para>A new elogind scope unit is created for the
+ session. If this is the first concurrent session of the user, an
+ implicit slice below <filename>user.slice</filename> is
+ automatically created and the scope placed into it. An instance
+ of the system service <filename>user@.service</filename>, which
+ runs the elogind user manager instance, is started.
+ </para></listitem>
+ </orderedlist>
+
+ <para>On logout, this module ensures the following:</para>
+
+ <orderedlist>
+ <listitem><para>If enabled in
+ <citerefentry><refentrytitle>logind.conf</refentrytitle>
+ <manvolnum>5</manvolnum></citerefentry>, all processes of the
+ session are terminated. If the last concurrent session of a user
+ ends, the user's elogind instance will be terminated too, and so
+ will the user's slice unit.</para></listitem>
+
+ <listitem><para>If the last concurrent session of a user ends,
+ the <varname>$XDG_RUNTIME_DIR</varname> directory and all its
+ contents are removed, too.</para></listitem>
+ </orderedlist>
+
+ <para>If the system was not booted up with elogind as init system,
+ this module does nothing and immediately returns
+ <constant>PAM_SUCCESS</constant>.</para>
+
+ </refsect1>
+
+ <refsect1>
+ <title>Options</title>
+
+ <para>The following options are understood:</para>
+
+ <variablelist class='pam-directives'>
+
+ <varlistentry>
+ <term><option>class=</option></term>
+
+ <listitem><para>Takes a string argument which sets the session
+ class. The XDG_SESSION_CLASS environmental variable takes
+ precedence. One of
+ <literal>user</literal>,
+ <literal>greeter</literal>,
+ <literal>lock-screen</literal> or
+ <literal>background</literal>. See
+ <citerefentry><refentrytitle>sd_session_get_class</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ for details about the session class.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>type=</option></term>
+
+ <listitem><para>Takes a string argument which sets the session
+ type. The XDG_SESSION_TYPE environmental variable takes
+ precedence. One of
+ <literal>unspecified</literal>,
+ <literal>tty</literal>,
+ <literal>x11</literal>,
+ <literal>wayland</literal> or
+ <literal>mir</literal>. See
+ <citerefentry><refentrytitle>sd_session_get_type</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ for details about the session type.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>debug<optional>=</optional></option></term>
+
+ <listitem><para>Takes an optional
+ boolean argument. If yes or without
+ the argument, the module will log
+ debugging information as it
+ operates.</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Module Types Provided</title>
+
+ <para>Only <option>session</option> is provided.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Environment</title>
+
+ <para>The following environment variables are set for the
+ processes of the user's session:</para>
+
+ <variablelist class='environment-variables'>
+ <varlistentry>
+ <term><varname>$XDG_SESSION_ID</varname></term>
+
+ <listitem><para>A session identifier, suitable to be used in
+ filenames. The string itself should be considered opaque,
+ although often it is just the audit session ID as reported by
+ <filename>/proc/self/sessionid</filename>. Each ID will be
+ assigned only once during machine uptime. It may hence be used
+ to uniquely label files or other resources of this
+ session.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$XDG_RUNTIME_DIR</varname></term>
+
+ <listitem><para>Path to a user-private user-writable directory
+ that is bound to the user login time on the machine. It is
+ automatically created the first time a user logs in and
+ removed on the user's final logout. If a user logs in twice at
+ the same time, both sessions will see the same
+ <varname>$XDG_RUNTIME_DIR</varname> and the same contents. If
+ a user logs in once, then logs out again, and logs in again,
+ the directory contents will have been lost in between, but
+ applications should not rely on this behavior and must be able
+ to deal with stale files. To store session-private data in
+ this directory, the user should include the value of
+ <varname>$XDG_SESSION_ID</varname> in the filename. This
+ directory shall be used for runtime file system objects such
+ as <constant>AF_UNIX</constant> sockets, FIFOs, PID files and
+ similar. It is guaranteed that this directory is local and
+ offers the greatest possible file system feature set the
+ operating system provides. For further details see the <ulink
+ url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG
+ Base Directory Specification</ulink>.</para></listitem>
+ </varlistentry>
+
+ </variablelist>
+
+ <para>The following environment variables are read by the module
+ and may be used by the PAM service to pass metadata to the
+ module:</para>
+
+ <variablelist class='environment-variables'>
+ <varlistentry>
+ <term><varname>$XDG_SESSION_TYPE</varname></term>
+
+ <listitem><para>The session type. This may be used instead of
+ <option>session=</option> on the module parameter line, and is
+ usually preferred.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$XDG_SESSION_CLASS</varname></term>
+
+ <listitem><para>The session class. This may be used instead of
+ <option>class=</option> on the module parameter line, and is
+ usually preferred.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$XDG_SESSION_DESKTOP</varname></term>
+
+ <listitem><para>A single, short identifier string for the
+ desktop environment. This may be used to indicate the session
+ desktop used, where this applies and if this information is
+ available. For example: <literal>GNOME</literal>, or
+ <literal>KDE</literal>. It is recommended to use the same
+ identifiers and capitalization as for
+ <varname>$XDG_CURRENT_DESKTOP</varname>, as defined by the
+ <ulink
+ url="http://standards.freedesktop.org/desktop-entry-spec/latest/">Desktop
+ Entry Specification</ulink>. (However, note that
+ <varname>$XDG_SESSION_DESKTOP</varname> only takes a single
+ item, and not a colon-separated list like
+ <varname>$XDG_CURRENT_DESKTOP</varname>.) See
+ <citerefentry><refentrytitle>sd_session_get_desktop</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ for more details.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$XDG_SEAT</varname></term>
+
+ <listitem><para>The seat name the session shall be registered
+ for, if any.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$XDG_VTNR</varname></term>
+
+ <listitem><para>The VT number the session shall be registered
+ for, if any. (Only applies to seats with a VT available, such
+ as <literal>seat0</literal>)</para></listitem>
+ </varlistentry>
+
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Example</title>
+
+ <programlisting>#%PAM-1.0
+auth required pam_unix.so
+auth required pam_nologin.so
+account required pam_unix.so
+password required pam_unix.so
+session required pam_unix.so
+session required pam_loginuid.so
+session required pam_elogind.so</programlisting>
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>logind</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>logind.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>loginctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>pam.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>pam.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>pam</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>pam_loginuid</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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_get_seats" conditional='HAVE_PAM'>
+
+ <refentryinfo>
+ <title>sd_get_seats</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_get_seats</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_get_seats</refname>
+ <refname>sd_get_sessions</refname>
+ <refname>sd_get_uids</refname>
+ <refname>sd_get_machine_names</refname>
+ <refpurpose>Determine available seats, sessions, logged in users and virtual machines/containers</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <systemd/sd-login.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_get_seats</function></funcdef>
+ <paramdef>char ***<parameter>seats</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_get_sessions</function></funcdef>
+ <paramdef>char ***<parameter>sessions</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_get_uids</function></funcdef>
+ <paramdef>uid_t **<parameter>users</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_get_machine_names</function></funcdef>
+ <paramdef>char ***<parameter>machines</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_get_seats()</function> may be used to determine
+ all currently available local seats. Returns a
+ <constant>NULL</constant> terminated array of seat identifiers.
+ The returned array and all strings it references 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>Similarly, <function>sd_get_sessions()</function> may be
+ used to determine all current login sessions.</para>
+
+ <para>Similarly, <function>sd_get_uids()</function> may be used to
+ determine all Unix users who currently have login sessions.</para>
+
+ <para>Similarly, <function>sd_get_machine_names()</function> may
+ be used to determine all current virtual machines and containers
+ on the system.</para>
+
+ <para>Note that the returned lists are not sorted and in an
+ undefined order.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success, <function>sd_get_seats()</function>,
+ <function>sd_get_sessions()</function>,
+ <function>sd_get_uids()</function> and
+ <function>sd_get_machine_names()</function> return the number of
+ entries in the arrays. On failure, these calls return a negative
+ errno-style error code.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Notes</title>
+
+ <para>The <function>sd_get_seats()</function>,
+ <function>sd_get_sessions()</function>,
+ <function>sd_get_uids()</function> and
+ <function>sd_get_machine_names()</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>
--- /dev/null
+<?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_pid_get_session" conditional='HAVE_PAM'>
+
+ <refentryinfo>
+ <title>sd_pid_get_session</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_pid_get_session</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_pid_get_session</refname>
+ <refname>sd_pid_get_unit</refname>
+ <refname>sd_pid_get_user_unit</refname>
+ <refname>sd_pid_get_owner_uid</refname>
+ <refname>sd_pid_get_machine_name</refname>
+ <refname>sd_pid_get_slice</refname>
+ <refname>sd_peer_get_session</refname>
+ <refname>sd_peer_get_unit</refname>
+ <refname>sd_peer_get_user_unit</refname>
+ <refname>sd_peer_get_owner_uid</refname>
+ <refname>sd_peer_get_machine_name</refname>
+ <refname>sd_peer_get_slice</refname>
+ <refpurpose>Determine session, service, owner of a
+ session, container/VM or slice of a specific
+ PID or socket peer</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <systemd/sd-login.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_pid_get_session</function></funcdef>
+ <paramdef>pid_t <parameter>pid</parameter></paramdef>
+ <paramdef>char **<parameter>session</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_pid_get_unit</function></funcdef>
+ <paramdef>pid_t <parameter>pid</parameter></paramdef>
+ <paramdef>char **<parameter>unit</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_pid_get_user_unit</function></funcdef>
+ <paramdef>pid_t <parameter>pid</parameter></paramdef>
+ <paramdef>char **<parameter>unit</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_pid_get_owner_uid</function></funcdef>
+ <paramdef>pid_t <parameter>pid</parameter></paramdef>
+ <paramdef>uid_t *<parameter>uid</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_pid_get_machine_name</function></funcdef>
+ <paramdef>pid_t <parameter>pid</parameter></paramdef>
+ <paramdef>char **<parameter>name</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_pid_get_slice</function></funcdef>
+ <paramdef>pid_t <parameter>pid</parameter></paramdef>
+ <paramdef>char **<parameter>slice</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_peer_get_session</function></funcdef>
+ <paramdef>int <parameter>fd</parameter></paramdef>
+ <paramdef>char **<parameter>session</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_peer_get_unit</function></funcdef>
+ <paramdef>int <parameter>fd</parameter></paramdef>
+ <paramdef>char **<parameter>unit</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_peer_get_user_unit</function></funcdef>
+ <paramdef>int <parameter>fd</parameter></paramdef>
+ <paramdef>char **<parameter>unit</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_peer_get_owner_uid</function></funcdef>
+ <paramdef>int <parameter>fd</parameter></paramdef>
+ <paramdef>uid_t *<parameter>uid</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_peer_get_machine_name</function></funcdef>
+ <paramdef>int <parameter>fd</parameter></paramdef>
+ <paramdef>char **<parameter>name</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_peer_get_slice</function></funcdef>
+ <paramdef>int <parameter>fd</parameter></paramdef>
+ <paramdef>char **<parameter>slice</parameter></paramdef>
+ </funcprototype>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_pid_get_session()</function> may be used to
+ determine the login session identifier of a process identified by
+ the specified process identifier. The session identifier is a
+ short string, suitable for usage in file system paths. Note that
+ not all processes are part of a login session (e.g. system service
+ processes, user processes that are shared between multiple
+ sessions of the same user, or kernel threads). For processes not
+ being part of a login session this function will fail. 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_pid_get_unit()</function> may be used to
+ determine the systemd system unit (i.e. system service) identifier
+ of a process identified by the specified PID. The unit name is a
+ short string, suitable for usage in file system paths. Note that
+ not all processes are part of a system unit/service (e.g. user
+ processes, or kernel threads). For processes not being part of a
+ systemd system unit this function will fail. (More specifically:
+ this call will not work for processes that are part of user units,
+ use <function>sd_pid_get_user_unit()</function> for that.) 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_pid_get_user_unit()</function> may be used to
+ determine the systemd user unit (i.e. user service) identifier of
+ a process identified by the specified PID. This is similar to
+ <function>sd_pid_get_unit()</function> but applies to user units
+ instead of system units.</para>
+
+ <para><function>sd_pid_get_owner_uid()</function> may be used to
+ determine the Unix user identifier of the owner of the session of
+ a process identified the specified PID. Note that this function
+ will succeed for user processes which are shared between multiple
+ login sessions of the same user, where
+ <function>sd_pid_get_session()</function> will fail. For processes
+ not being part of a login session and not being a shared process
+ of a user this function will fail.</para>
+
+ <para><function>sd_pid_get_machine_name()</function> may be used
+ to determine the name of the VM or container is a member of. The
+ machine name is a short string, suitable for usage in file system
+ paths. 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_pid_get_slice()</function> may be used to
+ determine the slice unit the process is a member of. See
+ <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ for details about slices. 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>If the <varname>pid</varname> parameter of any of these
+ functions is passed as 0, the operation is executed for the
+ calling process.</para>
+
+ <para>The <function>sd_peer_get_session()</function>,
+ <function>sd_peer_get_unit()</function>,
+ <function>sd_peer_get_user_unit()</function>,
+ <function>sd_peer_get_owner_uid()</function>,
+ <function>sd_peer_get_machine_name()</function> and
+ <function>sd_peer_get_slice()</function> calls operate similar to
+ their PID counterparts, but operate on a connected AF_UNIX socket
+ and retrieve information about the connected peer process.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success, these calls 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_pid_get_session()</function>,
+ <function>sd_pid_get_unit()</function>,
+ <function>sd_pid_get_user_unit()</function>,
+ <function>sd_pid_get_owner_uid()</function>,
+ <function>sd_pid_get_machine_name()</function>,
+ <function>sd_pid_get_slice()</function>,
+ <function>sd_peer_get_session()</function>,
+ <function>sd_peer_get_unit()</function>,
+ <function>sd_peer_get_user_unit()</function>,
+ <function>sd_peer_get_owner_uid()</function>,
+ <function>sd_peer_get_machine_name()</function> and
+ <function>sd_peer_get_slice()</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>
+
+ <para>Note that the login session identifier as
+ returned by <function>sd_pid_get_session()</function>
+ is completely unrelated to the process session
+ identifier as returned by
+ <citerefentry><refentrytitle>getsid</refentrytitle><manvolnum>2</manvolnum></citerefentry>.</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_is_active</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>getsid</refentrytitle><manvolnum>2</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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>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>
--- /dev/null
+<?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" conditional='HAVE_PAM'>
+
+ <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_is_remote</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_desktop</refname>
+ <refname>sd_session_get_display</refname>
+ <refname>sd_session_get_tty</refname>
+ <refname>sd_session_get_vt</refname>
+ <refname>sd_session_get_remote_host</refname>
+ <refname>sd_session_get_remote_user</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_is_remote</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_desktop</function></funcdef>
+ <paramdef>const char *<parameter>session</parameter></paramdef>
+ <paramdef>char **<parameter>desktop</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>
+
+ <funcprototype>
+ <funcdef>int <function>sd_session_get_remote_host</function></funcdef>
+ <paramdef>const char *<parameter>session</parameter></paramdef>
+ <paramdef>char **<parameter>remote_host</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_session_get_remote_user</function></funcdef>
+ <paramdef>const char *<parameter>session</parameter></paramdef>
+ <paramdef>char **<parameter>remote_user</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_session_get_tty</function></funcdef>
+ <paramdef>const char *<parameter>session</parameter></paramdef>
+ <paramdef>char **<parameter>tty</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_session_get_vt</function></funcdef>
+ <paramdef>const char *<parameter>session</parameter></paramdef>
+ <paramdef>unsigned int *<parameter>vt</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_is_remote()</function> 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.</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 project='man-pages'><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 project='man-pages'><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 project='man-pages'><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>wayland</literal>,
+ <literal>tty</literal>, <literal>mir</literal> or
+ <literal>unspecified</literal> and 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_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>,
+ <literal>lock-screen</literal>, or <literal>background</literal>
+ and 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_session_get_desktop()</function> may be used to
+ determine the brand of the desktop running on the session
+ identified by the specified session identifier. This field can be
+ set freely by desktop environments and does not follow any special
+ formatting. However, desktops are strongly recommended to use the
+ same identifiers and capitalization as for
+ <varname>$XDG_CURRENT_DESKTOP</varname>, as defined by the <ulink
+ url="http://standards.freedesktop.org/desktop-entry-spec/latest/">Desktop
+ Entry Specification</ulink>. 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_session_get_display()</function> 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
+ <citerefentry project='man-pages'><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ call after use.</para>
+
+ <para><function>sd_session_get_remote_host()</function> 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
+ <citerefentry project='man-pages'><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ call after use.</para>
+
+ <para><function>sd_session_get_remote_user()</function> 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
+ <citerefentry project='man-pages'><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ call after use. Note that this value is rarely known to the
+ system, and even then should not be relied on.</para>
+
+ <para><function>sd_session_get_tty()</function> 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
+ <citerefentry project='man-pages'><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ call after use.</para>
+
+ <para><function>sd_session_get_vt()</function> 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.</para>
+
+ <para>If the <varname>session</varname> parameter of any of these
+ functions is passed as <constant>NULL</constant>, 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> and
+ <function>sd_session_is_remote()</function> return a
+ positive integer; if it fails, 0. On success,
+ <function>sd_session_get_state()</function>,
+ <function>sd_session_get_uid()</function>,
+ <function>sd_session_get_seat()</function>,
+ <function>sd_session_get_service()</function>,
+ <function>sd_session_get_type()</function>,
+ <function>sd_session_get_class()</function>,
+ <function>sd_session_get_display()</function>,
+ <function>sd_session_get_remote_user()</function>,
+ <function>sd_session_get_remote_host()</function> and
+ <function>sd_session_get_tty()</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_state()</function>,
+ <function>sd_session_get_uid()</function>,
+ <function>sd_session_get_seat()</function>,
+ <function>sd_session_get_service()</function>,
+ <function>sd_session_get_type()</function>,
+ <function>sd_session_get_class()</function>,
+ <function>sd_session_get_display()</function>,
+ <function>sd_session_get_remote_host()</function>,
+ <function>sd_session_get_remote_user()</function> and
+ <function>sd_session_get_tty()</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_pid_get_session</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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_uid_get_state" conditional='HAVE_PAM'>
+
+ <refentryinfo>
+ <title>sd_uid_get_state</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_uid_get_state</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_uid_get_state</refname>
+ <refname>sd_uid_is_on_seat</refname>
+ <refname>sd_uid_get_sessions</refname>
+ <refname>sd_uid_get_seats</refname>
+ <refname>sd_uid_get_display</refname>
+ <refpurpose>Determine login state of a specific Unix user ID</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <systemd/sd-login.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_uid_get_state</function></funcdef>
+ <paramdef>uid_t <parameter>uid</parameter></paramdef>
+ <paramdef>char **<parameter>state</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_uid_is_on_seat</function></funcdef>
+ <paramdef>uid_t <parameter>uid</parameter></paramdef>
+ <paramdef>int <parameter>require_active</parameter></paramdef>
+ <paramdef>const char *<parameter>seat</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_uid_get_sessions</function></funcdef>
+ <paramdef>uid_t <parameter>uid</parameter></paramdef>
+ <paramdef>int <parameter>require_active</parameter></paramdef>
+ <paramdef>char ***<parameter>sessions</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_uid_get_seats</function></funcdef>
+ <paramdef>uid_t <parameter>uid</parameter></paramdef>
+ <paramdef>int <parameter>require_active</parameter></paramdef>
+ <paramdef>char ***<parameter>seats</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_uid_get_display</function></funcdef>
+ <paramdef>uid_t <parameter>uid</parameter></paramdef>
+ <paramdef>char **<parameter>session</parameter></paramdef>
+ </funcprototype>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_uid_get_state()</function> may be used to
+ determine the login state of a specific Unix user identifier. The
+ following states are currently known: <literal>offline</literal>
+ (user not logged in at all), <literal>lingering</literal> (user
+ not logged in, but some user services running),
+ <literal>online</literal> (user logged in, but not active, i.e.
+ has no session in the foreground), <literal>active</literal> (user
+ logged in, and has at least one active session, i.e. one session
+ in the foreground), <literal>closing</literal> (user not logged
+ in, and not lingering, but some processes 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. 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_uid_is_on_seat()</function> may be used to
+ determine whether a specific user is logged in or active on a
+ specific seat. Accepts a Unix user identifier and a seat
+ identifier string as parameters. The
+ <parameter>require_active</parameter> parameter is a boolean
+ value. If non-zero (true), this function will test if the user is
+ active (i.e. has a session that is in the foreground and accepting
+ user input) on the specified seat, otherwise (false) only if the
+ user is logged in (and possibly inactive) on the specified
+ seat.</para>
+
+ <para><function>sd_uid_get_sessions()</function> may be used to
+ determine the current sessions of the specified user. Accepts a
+ Unix user identifier as parameter. The
+ <parameter>require_active</parameter> parameter controls whether
+ the returned list shall consist of only those sessions where the
+ user is currently active (> 0), where the user is currently
+ online but possibly inactive (= 0), or logged in at all but
+ possibly closing the session (< 0). The call returns a
+ <constant>NULL</constant> terminated string array of session
+ identifiers in <parameter>sessions</parameter> which needs to be
+ freed by the caller with the libc
+ <citerefentry project='man-pages'><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ call after use, including all the strings referenced. If the
+ string array parameter is passed as <constant>NULL</constant>, the
+ array will not be filled in, but the return code still indicates
+ the number of current sessions. Note that instead of an empty
+ array <constant>NULL</constant> may be returned and should be
+ considered equivalent to an empty array.</para>
+
+ <para>Similarly, <function>sd_uid_get_seats()</function> may be
+ used to determine the list of seats on which the user currently
+ has sessions. Similar semantics apply, however note that the user
+ may have multiple sessions on the same seat as well as sessions
+ with no attached seat and hence the number of entries in the
+ returned array may differ from the one returned by
+ <function>sd_uid_get_sessions()</function>.</para>
+
+ <para><function>sd_uid_get_display()</function> returns the name
+ of the "primary" session of a user. If the user has graphical
+ sessions, it will be the oldest graphical session. Otherwise, it
+ will be the oldest open session.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success, <function>sd_uid_get_state()</function> returns
+ 0 or a positive integer. If the test succeeds,
+ <function>sd_uid_is_on_seat()</function> returns a positive
+ integer; if it fails, 0.
+ <function>sd_uid_get_sessions()</function> and
+ <function>sd_uid_get_seats()</function> return the number of
+ entries in the returned arrays.
+ <function>sd_uid_get_display()</function> returns a non-negative
+ code on success. On failure, these calls return a negative
+ errno-style error code.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Notes</title>
+
+ <para>Functions described here are available as a shared library,
+ and can be compiled and linked to using the
+ <constant>libsystemd</constant> <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ entry.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>History</title>
+
+ <para><function>sd_uid_get_state()</function>,
+ <function>sd_uid_is_on_seat()</function>,
+ <function>sd_uid_get_sessions()</function>, and
+ <function>sd_uid_get_seats()</function> functions were added in
+ systemd-31.</para>
+
+ <para><function>sd_uid_get_display()</function> was added in
+ systemd-213.</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_pid_get_owner_uid</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
~ianmdlvl / elogind.git / commitdiff