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  24 <a name="id1101967"></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">
  30   <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
  31     <tbody>
  32       <tr>
  33         <td class="listing_lines" align="right"><pre>1
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  77 45</pre></td>
  78         <td class="listing_code"><pre class="programlisting"><span class="normal">error </span><span class="symbol">=</span><span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">;</span>
  79 <span class="normal">res </span><span class="symbol">=</span><span class="normal"> </span><span class="function"><a href="/usr/share/gtk-doc/html/dbus-glib/dbus-glib-DBusGProxy.html#dbus-g-proxy-call">dbus_g_proxy_call</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">system_bus_proxy</span><span class="symbol">,</span>
  80 <span class="normal">                         </span><span class="string">"RequestName"</span><span class="symbol">,</span>
  81 <span class="normal">                         </span><span class="symbol">&amp;</span><span class="normal">error</span><span class="symbol">,</span>
  82 <span class="normal">                         <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-STRING:CAPS">G_TYPE_STRING</a></span><span class="symbol">,</span><span class="normal"> NAME_TO_CLAIM</span><span class="symbol">,</span>
  83 <span class="normal">                         <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-UINT:CAPS">G_TYPE_UINT</a></span><span class="symbol">,</span><span class="normal">   DBUS_NAME_FLAG_ALLOW_REPLACEMENT</span><span class="symbol">,</span>
  84 <span class="normal">                         <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-INVALID:CAPS">G_TYPE_INVALID</a></span><span class="symbol">,</span>
  85 <span class="normal">                         <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-UINT:CAPS">G_TYPE_UINT</a></span><span class="symbol">,</span><span class="normal">   </span><span class="symbol">&amp;</span><span class="normal">result</span><span class="symbol">,</span>
  86 <span class="normal">                         <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-INVALID:CAPS">G_TYPE_INVALID</a></span><span class="symbol">);</span>
  87 <span class="keyword">if</span><span class="normal"> </span><span class="symbol">(!</span><span class="normal">res</span><span class="symbol">)</span>
  88 <span class="normal">  </span><span class="cbracket">{</span>
  89 <span class="normal">    </span><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">error </span><span class="symbol">!=</span><span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">)</span>
  90 <span class="normal">      </span><span class="cbracket">{</span>
  91 <span class="normal">        </span><span class="function"><a href="./../glib/glib/glib-Message-Logging.html#g-warning">g_warning</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"Failed to acquire %s: %s"</span><span class="symbol">,</span>
  92 <span class="normal">                   NAME_TO_CLAIM</span><span class="symbol">,</span><span class="normal"> error</span><span class="symbol">-&gt;</span><span class="normal">message</span><span class="symbol">);</span>
  93 <span class="normal">        </span><span class="function"><a href="./../glib/glib/glib-Error-Reporting.html#g-error-free">g_error_free</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">error</span><span class="symbol">);</span>
  94 <span class="normal">      </span><span class="cbracket">}</span>
  95 <span class="normal">    </span><span class="keyword">else</span>
  96 <span class="normal">      </span><span class="cbracket">{</span>
  97 <span class="normal">        </span><span class="function"><a href="./../glib/glib/glib-Message-Logging.html#g-warning">g_warning</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"Failed to acquire %s"</span><span class="symbol">,</span><span class="normal"> NAME_TO_CLAIM</span><span class="symbol">);</span>
  98 <span class="normal">      </span><span class="cbracket">}</span>
  99 <span class="normal">    </span><span class="keyword">goto</span><span class="normal"> out</span><span class="symbol">;</span>
 100 <span class="normal">  </span><span class="cbracket">}</span>
 101
 102 <span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">result </span><span class="symbol">!=</span><span class="normal"> DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER</span><span class="symbol">)</span>
 103 <span class="normal">  </span><span class="cbracket">{</span>
 104 <span class="normal">    </span><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">error </span><span class="symbol">!=</span><span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">)</span>
 105 <span class="normal">      </span><span class="cbracket">{</span>
 106 <span class="normal">        </span><span class="function"><a href="./../glib/glib/glib-Message-Logging.html#g-warning">g_warning</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"Failed to acquire %s: %s"</span><span class="symbol">,</span>
 107 <span class="normal">                   NAME_TO_CLAIM</span><span class="symbol">,</span><span class="normal"> error</span><span class="symbol">-&gt;</span><span class="normal">message</span><span class="symbol">);</span>
 108 <span class="normal">        </span><span class="function"><a href="./../glib/glib/glib-Error-Reporting.html#g-error-free">g_error_free</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">error</span><span class="symbol">);</span>
 109 <span class="normal">      </span><span class="cbracket">}</span>
 110 <span class="normal">    </span><span class="keyword">else</span>
 111 <span class="normal">      </span><span class="cbracket">{</span>
 112 <span class="normal">        </span><span class="function"><a href="./../glib/glib/glib-Message-Logging.html#g-warning">g_warning</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"Failed to acquire %s"</span><span class="symbol">,</span><span class="normal"> NAME_TO_CLAIM</span><span class="symbol">);</span>
 113 <span class="normal">      </span><span class="cbracket">}</span>
 114 <span class="normal">    </span><span class="function">exit</span><span class="normal"> </span><span class="symbol">(</span><span class="number">1</span><span class="symbol">);</span>
 115 <span class="normal">  </span><span class="cbracket">}</span>
 116
 117 <span class="function"><a href="/usr/share/gtk-doc/html/dbus-glib/dbus-glib-DBusGProxy.html#dbus-g-proxy-add-signal">dbus_g_proxy_add_signal</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">system_bus_proxy</span><span class="symbol">,</span><span class="normal"> </span><span class="string">"NameLost"</span><span class="symbol">,</span>
 118 <span class="normal">                         <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-STRING:CAPS">G_TYPE_STRING</a></span><span class="symbol">,</span><span class="normal"> <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-INVALID:CAPS">G_TYPE_INVALID</a></span><span class="symbol">);</span>
 119 <span class="function"><a href="/usr/share/gtk-doc/html/dbus-glib/dbus-glib-DBusGProxy.html#dbus-g-proxy-connect-signal">dbus_g_proxy_connect_signal</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">system_bus_proxy</span><span class="symbol">,</span><span class="normal"> </span><span class="string">"NameLost"</span><span class="symbol">,</span>
 120 <span class="normal">                             </span><span class="function"><a href="./../gobject/gobject/gobject-Closures.html#G-CALLBACK:CAPS">G_CALLBACK</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">on_name_lost</span><span class="symbol">),</span><span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">,</span><span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">);</span>
 121
 122 <span class="comment">/* further setup ... */</span></pre></td>
 123       </tr>
 124     </tbody>
 125   </table>
 126 </div>
 127
 128 <p>
 129     </p>
 130 <p>
 131     While you can do things this way with GDBus too, using
 132     <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
 133     for this:
 134     </p>
 135 <div class="informalexample">
 136   <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
 137     <tbody>
 138       <tr>
 139         <td class="listing_lines" align="right"><pre>1
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 160 22</pre></td>
 161         <td class="listing_code"><pre class="programlisting"><span class="keyword">static</span><span class="normal"> </span><span class="type">void</span>
 162 <span class="function">on_name_acquired</span><span class="normal"> </span><span class="symbol">(</span><span class="usertype">GDBusConnection</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">connection</span><span class="symbol">,</span>
 163 <span class="normal">                  </span><span class="keyword">const</span><span class="normal"> </span><span class="usertype">gchar</span><span class="normal">     </span><span class="symbol">*</span><span class="normal">name</span><span class="symbol">,</span>
 164 <span class="normal">                  </span><span class="usertype">gpointer</span><span class="normal">         user_data</span><span class="symbol">)</span>
 165 <span class="cbracket">{</span>
 166 <span class="normal">  </span><span class="comment">/* further setup ... */</span>
 167 <span class="cbracket">}</span>
 168
 169 <span class="comment">/* ... */</span>
 170
 171 <span class="normal">  owner_id </span><span class="symbol">=</span><span class="normal"> </span><span class="function"><a href="gio-Owning-Bus-Names.html#g-bus-own-name">g_bus_own_name</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal"><a href="GDBusConnection.html#G-BUS-TYPE-SYSTEM:CAPS">G_BUS_TYPE_SYSTEM</a></span><span class="symbol">,</span>
 172 <span class="normal">                             NAME_TO_CLAIM</span><span class="symbol">,</span>
 173 <span class="normal">                             <a href="gio-Owning-Bus-Names.html#G-BUS-NAME-OWNER-FLAGS-ALLOW-REPLACEMENT:CAPS">G_BUS_NAME_OWNER_FLAGS_ALLOW_REPLACEMENT</a></span><span class="symbol">,</span>
 174 <span class="normal">                             on_bus_acquired</span><span class="symbol">,</span>
 175 <span class="normal">                             on_name_acquired</span><span class="symbol">,</span>
 176 <span class="normal">                             on_name_lost</span><span class="symbol">,</span>
 177 <span class="normal">                             <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">,</span>
 178 <span class="normal">                             <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">);</span>
 179
 180 <span class="normal">  </span><span class="function"><a href="./../glib/glib/glib-The-Main-Event-Loop.html#g-main-loop-run">g_main_loop_run</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">loop</span><span class="symbol">);</span>
 181
 182 <span class="normal">  </span><span class="function"><a href="gio-Owning-Bus-Names.html#g-bus-unown-name">g_bus_unown_name</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">owner_id</span><span class="symbol">);</span></pre></td>
 183       </tr>
 184     </tbody>
 185   </table>
 186 </div>
 187
 188 <p>
 189     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
 190     you to enter your mainloop to await the <code class="function">on_name_aquired()</code>
 191     callback. Also note that in order to avoid race conditions (e.g.
 192     when your service is activated by a method call), you have to export
 193     your manager object <span class="emphasis"><em>before</em></span> acquiring the
 194     name. The <code class="function">on_bus_acquired()</code> callback is the right place to do
 195     such preparations.
 196     </p>
 197 </div>
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