man/sd_get_seats.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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   8   Copyright 2010 Lennart Poettering
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  23
  24 <refentry id="sd_get_seats">
  25
  26         <refentryinfo>
  27                 <title>sd_get_seats</title>
  28                 <productname>systemd</productname>
  29
  30                 <authorgroup>
  31                         <author>
  32                                 <contrib>Developer</contrib>
  33                                 <firstname>Lennart</firstname>
  34                                 <surname>Poettering</surname>
  35                                 <email>lennart@poettering.net</email>
  36                         </author>
  37                 </authorgroup>
  38         </refentryinfo>
  39
  40         <refmeta>
  41                 <refentrytitle>sd_get_seats</refentrytitle>
  42                 <manvolnum>3</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>sd_get_seats</refname>
  47                 <refname>sd_get_sessions</refname>
  48                 <refname>sd_get_uids</refname>
  49                 <refpurpose>Determine available seats, sessions and logged in users</refpurpose>
  50         </refnamediv>
  51
  52         <refsynopsisdiv>
  53                 <funcsynopsis>
  54                         <funcsynopsisinfo>#include &lt;systemd/sd-login.h&gt;</funcsynopsisinfo>
  55
  56                         <funcprototype>
  57                                 <funcdef>int <function>sd_get_seats</function></funcdef>
  58                                 <paramdef>char*** <parameter>seats</parameter></paramdef>
  59                         </funcprototype>
  60
  61                         <funcprototype>
  62                                 <funcdef>int <function>sd_get_sessions</function></funcdef>
  63                                 <paramdef>char*** <parameter>sessions</parameter></paramdef>
  64                         </funcprototype>
  65
  66                         <funcprototype>
  67                                 <funcdef>int <function>sd_get_uids</function></funcdef>
  68                                 <paramdef>char*** <parameter>sessions</parameter></paramdef>
  69                         </funcprototype>
  70
  71                 </funcsynopsis>
  72         </refsynopsisdiv>
  73
  74         <refsect1>
  75                 <title>Description</title>
  76
  77                 <para><function>sd_get_seats()</function> may be used
  78                 to determine all currently available local
  79                 seats. Returns an array of seat identifiers. The
  80                 returned array and all strings it references need to
  81                 be freed with the libc
  82                 <citerefentry><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
  83                 call after use.</para>
  84
  85                 <para>Similar, <function>sd_get_sessions()</function> may
  86                 be used to determine all current login sessions.</para>
  87
  88                 <para>Similar, <function>sd_get_uids()</function> may
  89                 be used to determine all Unix users who currently have login sessions.</para>
  90         </refsect1>
  91
  92         <refsect1>
  93                 <title>Return Value</title>
  94
  95                 <para>On success <function>sd_get_seats()</function>,
  96                 <function>sd_get_sessions()</function> and
  97                 <function>sd_get_uids()</function> return the number
  98                 of entries in the arrays. On failure, these calls
  99                 return a negative errno-style error code.</para>
 100         </refsect1>
 101
 102         <refsect1>
 103                 <title>Notes</title>
 104
 105                 <para>The <function>sd_get_seats()</function>,
 106                 <function>sd_get_sessions()</function> and
 107                 <function>sd_get_uids()</function> interfaces
 108                 are available as shared library, which can be compiled
 109                 and linked to with the
 110                 <literal>libsystemd-login</literal>
 111                 <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 112                 file.</para>
 113         </refsect1>
 114
 115         <refsect1>
 116                 <title>See Also</title>
 117
 118                 <para>
 119                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 120                         <citerefentry><refentrytitle>sd-login</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 121                         <citerefentry><refentrytitle>sd_session_get_seat</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 122                 </para>
 123         </refsect1>
 124
 125 </refentry>