docs/reference/gio/html/ch31s03.html

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  23 <div class="titlepage"><div><div><h2 class="title" style="clear: both">
  24 <a name="idp76275952"></a>Owning bus names</h2></div></div></div>
  25 <p>
  26       Using dbus-glib, you typically call RequestName manually
  27       to own a name, like in the following excerpt:
  28       </p>
  29 <div class="informalexample"><pre class="programlisting">
  30   error = NULL;
  31   res = dbus_g_proxy_call (system_bus_proxy,
  32                            "RequestName",
  33                            &amp;error,
  34                            G_TYPE_STRING, NAME_TO_CLAIM,
  35                            G_TYPE_UINT,   DBUS_NAME_FLAG_ALLOW_REPLACEMENT,
  36                            G_TYPE_INVALID,
  37                            G_TYPE_UINT,   &amp;result,
  38                            G_TYPE_INVALID);
  39   if (!res)
  40     {
  41       if (error != NULL)
  42         {
  43           g_warning ("Failed to acquire %s: %s",
  44                      NAME_TO_CLAIM, error-&gt;message);
  45           g_error_free (error);
  46         }
  47       else
  48         {
  49           g_warning ("Failed to acquire %s", NAME_TO_CLAIM);
  50         }
  51       goto out;
  52     }
  53
  54   if (result != DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER)
  55     {
  56       if (error != NULL)
  57         {
  58           g_warning ("Failed to acquire %s: %s",
  59                      NAME_TO_CLAIM, error-&gt;message);
  60           g_error_free (error);
  61         }
  62       else
  63         {
  64           g_warning ("Failed to acquire %s", NAME_TO_CLAIM);
  65         }
  66       exit (1);
  67     }
  68
  69   dbus_g_proxy_add_signal (system_bus_proxy, "NameLost",
  70                            G_TYPE_STRING, G_TYPE_INVALID);
  71   dbus_g_proxy_connect_signal (system_bus_proxy, "NameLost",
  72                                G_CALLBACK (on_name_lost), NULL, NULL);
  73
  74   /* further setup ... */
  75
  76       </pre></div>
  77 <p>
  78     </p>
  79 <p>
  80     While you can do things this way with GDBus too, using
  81     <a class="link" href="GDBusProxy.html#g-dbus-proxy-call-sync" title="g_dbus_proxy_call_sync ()"><code class="function">g_dbus_proxy_call_sync()</code></a>, it is much nicer to use the high-level API
  82     for this:
  83     </p>
  84 <div class="informalexample"><pre class="programlisting">
  85 static void
  86 on_name_acquired (GDBusConnection *connection,
  87                   const gchar     *name,
  88                   gpointer         user_data)
  89 {
  90   /* further setup ... */
  91 }
  92
  93 /* ... */
  94
  95   owner_id = g_bus_own_name (G_BUS_TYPE_SYSTEM,
  96                              NAME_TO_CLAIM,
  97                              G_BUS_NAME_OWNER_FLAGS_ALLOW_REPLACEMENT,
  98                              on_bus_acquired,
  99                              on_name_acquired,
 100                              on_name_lost,
 101                              NULL,
 102                              NULL);
 103
 104   g_main_loop_run (loop);
 105
 106   g_bus_unown_name (owner_id);
 107
 108     </pre></div>
 109 <p>
 110     Note that <a class="link" href="gio-Owning-Bus-Names.html#g-bus-own-name" title="g_bus_own_name ()"><code class="function">g_bus_own_name()</code></a> works asynchronously and requires
 111     you to enter your mainloop to await the <code class="function">on_name_aquired()</code>
 112     callback. Also note that in order to avoid race conditions (e.g.
 113     when your service is activated by a method call), you have to export
 114     your manager object <span class="emphasis"><em>before</em></span> acquiring the
 115     name. The <code class="function">on_bus_acquired()</code> callback is the right place to do
 116     such preparations.
 117     </p>
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