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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="id-1.5.5.4"></a>Owning bus names</h2></div></div></div>
<p>
Using dbus-glib, you typically call RequestName manually
to own a name, like in the following excerpt:
</p>
<div class="informalexample">
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<td class="listing_code"><pre class="programlisting"><span class="n">error</span> <span class="o">=</span> <span class="nb">NULL</span><span class="p">;</span>
<span class="n">res</span> <span class="o">=</span> <span class="n">dbus_g_proxy_call</span> <span class="p">(</span><span class="n">system_bus_proxy</span><span class="p">,</span>
<span class="s">"RequestName"</span><span class="p">,</span>
<span class="o">&</span><span class="n">error</span><span class="p">,</span>
<span class="n">G_TYPE_STRING</span><span class="p">,</span> <span class="n">NAME_TO_CLAIM</span><span class="p">,</span>
<span class="n">G_TYPE_UINT</span><span class="p">,</span> <span class="n">DBUS_NAME_FLAG_ALLOW_REPLACEMENT</span><span class="p">,</span>
<span class="n">G_TYPE_INVALID</span><span class="p">,</span>
<span class="n">G_TYPE_UINT</span><span class="p">,</span> <span class="o">&</span><span class="n">result</span><span class="p">,</span>
<span class="n">G_TYPE_INVALID</span><span class="p">);</span>
<span class="k">if</span> <span class="p">(</span><span class="o">!</span><span class="n">res</span><span class="p">)</span>
<span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="n">error</span> <span class="o">!=</span> <span class="nb">NULL</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">g_warning</span> <span class="p">(</span><span class="s">"Failed to acquire %s: %s"</span><span class="p">,</span>
<span class="n">NAME_TO_CLAIM</span><span class="p">,</span> <span class="n">error</span><span class="o">-></span><span class="n">message</span><span class="p">);</span>
<span class="n">g_error_free</span> <span class="p">(</span><span class="n">error</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">else</span>
<span class="p">{</span>
<span class="n">g_warning</span> <span class="p">(</span><span class="s">"Failed to acquire %s"</span><span class="p">,</span> <span class="n">NAME_TO_CLAIM</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">goto</span> <span class="n">out</span><span class="p">;</span>
<span class="p">}</span>
<span class="k">if</span> <span class="p">(</span><span class="n">result</span> <span class="o">!=</span> <span class="n">DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER</span><span class="p">)</span>
<span class="p">{</span>
<span class="k">if</span> <span class="p">(</span><span class="n">error</span> <span class="o">!=</span> <span class="nb">NULL</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">g_warning</span> <span class="p">(</span><span class="s">"Failed to acquire %s: %s"</span><span class="p">,</span>
<span class="n">NAME_TO_CLAIM</span><span class="p">,</span> <span class="n">error</span><span class="o">-></span><span class="n">message</span><span class="p">);</span>
<span class="n">g_error_free</span> <span class="p">(</span><span class="n">error</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">else</span>
<span class="p">{</span>
<span class="n">g_warning</span> <span class="p">(</span><span class="s">"Failed to acquire %s"</span><span class="p">,</span> <span class="n">NAME_TO_CLAIM</span><span class="p">);</span>
<span class="p">}</span>
<span class="n">exit</span> <span class="p">(</span><span class="mi">1</span><span class="p">);</span>
<span class="p">}</span>
<span class="n">dbus_g_proxy_add_signal</span> <span class="p">(</span><span class="n">system_bus_proxy</span><span class="p">,</span> <span class="s">"NameLost"</span><span class="p">,</span>
<span class="n">G_TYPE_STRING</span><span class="p">,</span> <span class="n">G_TYPE_INVALID</span><span class="p">);</span>
<span class="n">dbus_g_proxy_connect_signal</span> <span class="p">(</span><span class="n">system_bus_proxy</span><span class="p">,</span> <span class="s">"NameLost"</span><span class="p">,</span>
<span class="n">G_CALLBACK</span> <span class="p">(</span><span class="n">on_name_lost</span><span class="p">),</span> <span class="nb">NULL</span><span class="p">,</span> <span class="nb">NULL</span><span class="p">);</span>
<span class="cm">/* further setup ... */</span></pre></td>
</tr>
</tbody>
</table>
</div>
<p>
</p>
<p>
While you can do things this way with GDBus too, using
<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
for this:
</p>
<div class="informalexample">
<table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td class="listing_lines" align="right"><pre>1
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<td class="listing_code"><pre class="programlisting"><span class="k">static</span> <span class="kt">void</span>
<span class="nf">on_name_acquired</span> <span class="p">(</span><span class="n">GDBusConnection</span> <span class="o">*</span><span class="n">connection</span><span class="p">,</span>
<span class="k">const</span> <span class="n">gchar</span> <span class="o">*</span><span class="n">name</span><span class="p">,</span>
<span class="n">gpointer</span> <span class="n">user_data</span><span class="p">)</span>
<span class="p">{</span>
<span class="cm">/* further setup ... */</span>
<span class="p">}</span>
<span class="cm">/* ... */</span>
<span class="n">owner_id</span> <span class="o">=</span> <span class="n">g_bus_own_name</span> <span class="p">(</span><span class="n">G_BUS_TYPE_SYSTEM</span><span class="p">,</span>
<span class="n">NAME_TO_CLAIM</span><span class="p">,</span>
<span class="n">G_BUS_NAME_OWNER_FLAGS_ALLOW_REPLACEMENT</span><span class="p">,</span>
<span class="n">on_bus_acquired</span><span class="p">,</span>
<span class="n">on_name_acquired</span><span class="p">,</span>
<span class="n">on_name_lost</span><span class="p">,</span>
<span class="nb">NULL</span><span class="p">,</span>
<span class="nb">NULL</span><span class="p">);</span>
<span class="n">g_main_loop_run</span> <span class="p">(</span><span class="n">loop</span><span class="p">);</span>
<span class="n">g_bus_unown_name</span> <span class="p">(</span><span class="n">owner_id</span><span class="p">);</span></pre></td>
</tr>
</tbody>
</table>
</div>
<p>
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
you to enter your mainloop to await the <code class="function">on_name_aquired()</code>
callback. Also note that in order to avoid race conditions (e.g.
when your service is activated by a method call), you have to export
your manager object <span class="emphasis"><em>before</em></span> acquiring the
name. The <code class="function">on_bus_acquired()</code> callback is the right place to do
such preparations.
</p>
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