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   5 <title>Creating proxies for well-known names</title>
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  24 <a name="id1053820"></a>Creating proxies for well-known names</h2></div></div></div>
  25 <p>
  26       dbus-glib lets you create proxy objects for well-known names, like the
  27       following example:
  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
  34 2
  35 3
  36 4</pre></td>
  37         <td class="listing_code"><pre class="programlisting"><span class="normal">proxy </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-new-for-name">dbus_g_proxy_new_for_name</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">system_bus_connection</span><span class="symbol">,</span>
  38 <span class="normal">                                   </span><span class="string">"org.freedesktop.Accounts"</span><span class="symbol">,</span>
  39 <span class="normal">                                   </span><span class="string">"/org/freedesktop/Accounts"</span><span class="symbol">,</span>
  40 <span class="normal">                                   </span><span class="string">"org.freedesktop.Accounts"</span><span class="symbol">);</span></pre></td>
  41       </tr>
  42     </tbody>
  43   </table>
  44 </div>
  45
  46 <p>
  47       For a <a href="/usr/share/gtk-doc/html/dbus-glib/dbus-glib-DBusGProxy.html#DBusGProxy"><span class="type">DBusGProxy</span></a> constructed like this, method calls will be sent to
  48       the current owner of the name, and that owner can change over time.
  49     </p>
  50 <p>
  51       The same can be achieved with <a class="link" href="GDBusProxy.html" title="GDBusProxy"><span class="type">GDBusProxy</span></a>:
  52       </p>
  53 <div class="informalexample">
  54   <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
  55     <tbody>
  56       <tr>
  57         <td class="listing_lines" align="right"><pre>1
  58 2
  59 3
  60 4
  61 5
  62 6
  63 7
  64 8
  65 9</pre></td>
  66         <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>
  67 <span class="normal">proxy </span><span class="symbol">=</span><span class="normal"> </span><span class="function"><a href="GDBusProxy.html#g-dbus-proxy-new-for-bus-sync">g_dbus_proxy_new_for_bus_sync</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>
  68 <span class="normal">                                       <a href="GDBusProxy.html#G-DBUS-PROXY-FLAGS-NONE:CAPS">G_DBUS_PROXY_FLAGS_NONE</a></span><span class="symbol">,</span>
  69 <span class="normal">                                       <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">,</span><span class="normal"> </span><span class="comment">/* GDBusInterfaceInfo */</span>
  70 <span class="normal">                                       </span><span class="string">"org.freedesktop.Accounts"</span><span class="symbol">,</span>
  71 <span class="normal">                                       </span><span class="string">"/org/freedesktop/Accounts"</span><span class="symbol">,</span>
  72 <span class="normal">                                       </span><span class="string">"org.freedesktop.Accounts"</span><span class="symbol">,</span>
  73 <span class="normal">                                       <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">,</span><span class="normal"> </span><span class="comment">/* GCancellable */</span>
  74 <span class="normal">                                       </span><span class="symbol">&amp;</span><span class="normal">error</span><span class="symbol">);</span></pre></td>
  75       </tr>
  76     </tbody>
  77   </table>
  78 </div>
  79
  80 <p>
  81       For an added layer of safety, you can specify what D-Bus
  82       interface the proxy is expected to conform to by using the
  83       <a class="link" href="gio-D-Bus-Introspection-Data.html#GDBusInterfaceInfo"><span class="type">GDBusInterfaceInfo</span></a> type.  Additionally, <a class="link" href="GDBusProxy.html" title="GDBusProxy"><span class="type">GDBusProxy</span></a> loads,
  84       caches and tracks changes to the D-Bus properties on the remote
  85       object. It also sets up match rules so D-Bus signals from the
  86       remote object are delivered locally.
  87     </p>
  88 <p>
  89       The <a class="link" href="GDBusProxy.html" title="GDBusProxy"><span class="type">GDBusProxy</span></a> type normally isn't used directly - instead
  90       proxies subclassing <a class="link" href="GDBusProxy.html" title="GDBusProxy"><span class="type">GDBusProxy</span></a> generated by <span class="command"><strong><a href="gdbus-codegen.html">gdbus-codegen</a></strong></span> is used, see <a class="xref" href="ch30s05.html#gdbus-example-gdbus-codegen" title="Using gdbus-codegen">the section called “Using gdbus-codegen”</a>
  91     </p>
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