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<tr><td colspan="5" class="shortcuts"><nobr><a href="#id2659088" class="shortcut">Top</a>
 | 
<a href="#id2659419" class="shortcut">Description</a>
 | 
<a href="#id2659372" class="shortcut">Object Hierarchy</a>
 | 
<a href="#id2659396" class="shortcut">Implemented Interfaces</a></nobr></td></tr>
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<div class="refentry" lang="en">
<a name="GTypeModule"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2>
<a name="id2659088"></a><span class="refentrytitle">GTypeModule</span>
</h2>
<p>GTypeModule — Type loading modules</p>
</td>
<td valign="top" align="right"></td>
</tr></table></div>
<div class="refsynopsisdiv">
<h2>Synopsis</h2>
<pre class="synopsis">
#include <glib-object.h>
<a href="GTypeModule.html#GTypeModule-struct">GTypeModule</a>;
<a href="GTypeModule.html#GTypeModuleClass">GTypeModuleClass</a>;
<a
href="../glib/glib-Basic-Types.html#gboolean"
>gboolean</a> <a href="GTypeModule.html#g-type-module-use">g_type_module_use</a> (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module);
void <a href="GTypeModule.html#g-type-module-unuse">g_type_module_unuse</a> (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module);
void <a href="GTypeModule.html#g-type-module-set-name">g_type_module_set_name</a> (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module,
const <a
href="../glib/glib-Basic-Types.html#gchar"
>gchar</a> *name);
<a href="gobject-Type-Information.html#GType">GType</a> <a href="GTypeModule.html#g-type-module-register-type">g_type_module_register_type</a> (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module,
<a href="gobject-Type-Information.html#GType">GType</a> parent_type,
const <a
href="../glib/glib-Basic-Types.html#gchar"
>gchar</a> *type_name,
const <a href="gobject-Type-Information.html#GTypeInfo">GTypeInfo</a> *type_info,
<a href="gobject-Type-Information.html#GTypeFlags">GTypeFlags</a> flags);
void <a href="GTypeModule.html#g-type-module-add-interface">g_type_module_add_interface</a> (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module,
<a href="gobject-Type-Information.html#GType">GType</a> instance_type,
<a href="gobject-Type-Information.html#GType">GType</a> interface_type,
const <a href="gobject-Type-Information.html#GInterfaceInfo">GInterfaceInfo</a> *interface_info);
<a href="gobject-Type-Information.html#GType">GType</a> <a href="GTypeModule.html#g-type-module-register-enum">g_type_module_register_enum</a> (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module,
const <a
href="../glib/glib-Basic-Types.html#gchar"
>gchar</a> *name,
const <a href="gobject-Enumeration-and-Flag-Types.html#GEnumValue">GEnumValue</a> *const _static_values);
<a href="gobject-Type-Information.html#GType">GType</a> <a href="GTypeModule.html#g-type-module-register-flags">g_type_module_register_flags</a> (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module,
const <a
href="../glib/glib-Basic-Types.html#gchar"
>gchar</a> *name,
const <a href="gobject-Enumeration-and-Flag-Types.html#GFlagsValue">GFlagsValue</a> *const _static_values);
</pre>
</div>
<div class="refsect1" lang="en">
<a name="id2659372"></a><h2>Object Hierarchy</h2>
<pre class="synopsis">
<a href="gobject-The-Base-Object-Type.html#GObject">GObject</a>
+----GTypeModule
</pre>
</div>
<div class="refsect1" lang="en">
<a name="id2659396"></a><h2>Implemented Interfaces</h2>
<p>
GTypeModule implements
<a href="GTypePlugin.html" title="GTypePlugin">GTypePlugin</a>.</p>
</div>
<div class="refsect1" lang="en">
<a name="id2659419"></a><h2>Description</h2>
<p>
<a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a> provides a simple implementation of the <a href="GTypePlugin.html" title="GTypePlugin"><span class="type">GTypePlugin</span></a>
interface. The model of <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a> is a dynamically loaded module
which implements some number of types and interface
implementations. When the module is loaded, it registers its types
and interfaces using <a href="GTypeModule.html#g-type-module-register-type"><code class="function">g_type_module_register_type()</code></a> and
<a href="GTypeModule.html#g-type-module-add-interface"><code class="function">g_type_module_add_interface()</code></a>. As long as any instances of these
types and interface implementations are in use, the module is kept
loaded. When the types and interfaces are gone, the module may be
unloaded. If the types and interfaces become used again, the module
will be reloaded. Note that the last unref can not happen in module
code, since that would lead to the caller's code being unloaded before
<a href="gobject-The-Base-Object-Type.html#g-object-unref"><code class="function">g_object_unref()</code></a> returns to it.
</p>
<p>
Keeping track of whether the module should be loaded or not is done by
using a use count - it starts at zero, and whenever it is greater than
zero, the module is loaded. The use count is maintained internally by
the type system, but also can be explicitly controlled by
<a href="GTypeModule.html#g-type-module-use"><code class="function">g_type_module_use()</code></a> and <a href="GTypeModule.html#g-type-module-unuse"><code class="function">g_type_module_unuse()</code></a>. Typically, when loading
a module for the first type, <a href="GTypeModule.html#g-type-module-use"><code class="function">g_type_module_use()</code></a> will be used to load
it so that it can initialize its types. At some later point, when the
module no longer needs to be loaded except for the type
implementations it contains, <a href="GTypeModule.html#g-type-module-unuse"><code class="function">g_type_module_unuse()</code></a> is called.
</p>
<p>
<a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a> does not actually provide any implementation of module
loading and unloading. To create a particular module type you must
derive from <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a> and implement the load and unload functions
in <a href="GTypeModule.html#GTypeModuleClass"><span class="type">GTypeModuleClass</span></a>.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2659585"></a><h2>Details</h2>
<div class="refsect2" lang="en">
<a name="id2659595"></a><h3>
<a name="GTypeModule-struct"></a>GTypeModule</h3>
<a class="indexterm" name="id2659608"></a><pre class="programlisting">typedef struct {
gchar *name;
} GTypeModule;
</pre>
<p>
The members of the <span class="structname">GTypeModule</span> structure should not
be accessed directly, except for the <em class="parameter"><code>name</code></em> field.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td>
<span class="term"><a
href="../glib/glib-Basic-Types.html#gchar"
>gchar</a> *<em class="structfield"><code>name</code></em>;</span></td>
<td>the name of the module
</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2659659"></a><h3>
<a name="GTypeModuleClass"></a>GTypeModuleClass</h3>
<a class="indexterm" name="id2659671"></a><pre class="programlisting">typedef struct {
GObjectClass parent_class;
gboolean (* load) (GTypeModule *module);
void (* unload) (GTypeModule *module);
} GTypeModuleClass;
</pre>
<p>
In order to implement dynamic loading of types based on <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a>,
the <em class="parameter"><code>load</code></em> and <em class="parameter"><code>unload</code></em> functions in <a href="GTypeModule.html#GTypeModuleClass"><span class="type">GTypeModuleClass</span></a> must be implemented.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><a href="gobject-The-Base-Object-Type.html#GObjectClass">GObjectClass</a> <em class="structfield"><code>parent_class</code></em>;</span></td>
<td>the parent class
</td>
</tr>
<tr>
<td>
<span class="term"><em class="structfield"><code>load</code></em> ()</span></td>
<td>loads the module and registers one or more types using
<a href="GTypeModule.html#g-type-module-register-type"><code class="function">g_type_module_register_type()</code></a>.
</td>
</tr>
<tr>
<td>
<span class="term"><em class="structfield"><code>unload</code></em> ()</span></td>
<td>unloads the module
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2659784"></a><h3>
<a name="g-type-module-use"></a>g_type_module_use ()</h3>
<a class="indexterm" name="id2659798"></a><pre class="programlisting"><a
href="../glib/glib-Basic-Types.html#gboolean"
>gboolean</a> g_type_module_use (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module);</pre>
<p>
Increases the use count of a <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a> by one. If the
use count was zero before, the plugin will be loaded.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>module</code></em> :</span></td>
<td>a <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a>
</td>
</tr>
<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td>
<td>
<a
href="../glib/glib-Standard-Macros.html#FALSE:CAPS"
><code class="literal">FALSE</code></a> if the plugin needed to be loaded and
loading the plugin failed.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2659881"></a><h3>
<a name="g-type-module-unuse"></a>g_type_module_unuse ()</h3>
<a class="indexterm" name="id2659894"></a><pre class="programlisting">void g_type_module_unuse (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module);</pre>
<p>
Decreases the use count of a <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a> by one. If the
result is zero, the module will be unloaded. (However, the
<a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a> will not be freed, and types associated with the
<a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a> are not unregistered. Once a <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a> is
initialized, it must exist forever.)
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td>
<span class="term"><em class="parameter"><code>module</code></em> :</span></td>
<td>a <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a>
</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2659982"></a><h3>
<a name="g-type-module-set-name"></a>g_type_module_set_name ()</h3>
<a class="indexterm" name="id2659996"></a><pre class="programlisting">void g_type_module_set_name (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module,
const <a
href="../glib/glib-Basic-Types.html#gchar"
>gchar</a> *name);</pre>
<p>
Sets the name for a <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>module</code></em> :</span></td>
<td>a <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a>.
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>name</code></em> :</span></td>
<td>a human-readable name to use in error messages.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2660080"></a><h3>
<a name="g-type-module-register-type"></a>g_type_module_register_type ()</h3>
<a class="indexterm" name="id2660094"></a><pre class="programlisting"><a href="gobject-Type-Information.html#GType">GType</a> g_type_module_register_type (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module,
<a href="gobject-Type-Information.html#GType">GType</a> parent_type,
const <a
href="../glib/glib-Basic-Types.html#gchar"
>gchar</a> *type_name,
const <a href="gobject-Type-Information.html#GTypeInfo">GTypeInfo</a> *type_info,
<a href="gobject-Type-Information.html#GTypeFlags">GTypeFlags</a> flags);</pre>
<p>
Looks up or registers a type that is implemented with a particular
type plugin. If a type with name <em class="parameter"><code>type_name</code></em> was previously registered,
the <a href="gobject-Type-Information.html#GType"><span class="type">GType</span></a> identifier for the type is returned, otherwise the type
is newly registered, and the resulting <a href="gobject-Type-Information.html#GType"><span class="type">GType</span></a> identifier returned.
</p>
<p>
When reregistering a type (typically because a module is unloaded
then reloaded, and reinitialized), <em class="parameter"><code>module</code></em> and <em class="parameter"><code>parent_type</code></em> must
be the same as they were previously.
</p>
<p>
As long as any instances of the type exist, the type plugin will
not be unloaded.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>module</code></em> :</span></td>
<td> a <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a>
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>parent_type</code></em> :</span></td>
<td> the type for the parent class
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>type_name</code></em> :</span></td>
<td> name for the type
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>type_info</code></em> :</span></td>
<td> type information structure
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>flags</code></em> :</span></td>
<td> flags field providing details about the type
</td>
</tr>
<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td>
<td>the new or existing type ID
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2660294"></a><h3>
<a name="g-type-module-add-interface"></a>g_type_module_add_interface ()</h3>
<a class="indexterm" name="id2660307"></a><pre class="programlisting">void g_type_module_add_interface (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module,
<a href="gobject-Type-Information.html#GType">GType</a> instance_type,
<a href="gobject-Type-Information.html#GType">GType</a> interface_type,
const <a href="gobject-Type-Information.html#GInterfaceInfo">GInterfaceInfo</a> *interface_info);</pre>
<p>
Registers an additional interface for a type, whose interface
lives in the given type plugin. If the interface was already registered
for the type in this plugin, nothing will be done.
</p>
<p>
As long as any instances of the type exist, the type plugin will
not be unloaded.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>module</code></em> :</span></td>
<td>a <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a>
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>instance_type</code></em> :</span></td>
<td>type to which to add the interface.
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>interface_type</code></em> :</span></td>
<td>interface type to add
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>interface_info</code></em> :</span></td>
<td>type information structure
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2660435"></a><h3>
<a name="g-type-module-register-enum"></a>g_type_module_register_enum ()</h3>
<a class="indexterm" name="id2660451"></a><pre class="programlisting"><a href="gobject-Type-Information.html#GType">GType</a> g_type_module_register_enum (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module,
const <a
href="../glib/glib-Basic-Types.html#gchar"
>gchar</a> *name,
const <a href="gobject-Enumeration-and-Flag-Types.html#GEnumValue">GEnumValue</a> *const _static_values);</pre>
<p>
Looks up or registers an enumeration that is implemented with a particular
type plugin. If a type with name <em class="parameter"><code>type_name</code></em> was previously registered,
the <a href="gobject-Type-Information.html#GType"><span class="type">GType</span></a> identifier for the type is returned, otherwise the type
is newly registered, and the resulting <a href="gobject-Type-Information.html#GType"><span class="type">GType</span></a> identifier returned.
</p>
<p>
As long as any instances of the type exist, the type plugin will
not be unloaded.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>module</code></em> :</span></td>
<td> a <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a>
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>name</code></em> :</span></td>
<td> name for the type
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>_static_values</code></em> :</span></td>
<td>
</td>
</tr>
<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td>
<td>the new or existing type ID
</td>
</tr>
</tbody>
</table></div>
<p>Since 2.6
</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2660594"></a><h3>
<a name="g-type-module-register-flags"></a>g_type_module_register_flags ()</h3>
<a class="indexterm" name="id2660610"></a><pre class="programlisting"><a href="gobject-Type-Information.html#GType">GType</a> g_type_module_register_flags (<a href="GTypeModule.html" title="GTypeModule">GTypeModule</a> *module,
const <a
href="../glib/glib-Basic-Types.html#gchar"
>gchar</a> *name,
const <a href="gobject-Enumeration-and-Flag-Types.html#GFlagsValue">GFlagsValue</a> *const _static_values);</pre>
<p>
Looks up or registers a flags type that is implemented with a particular
type plugin. If a type with name <em class="parameter"><code>type_name</code></em> was previously registered,
the <a href="gobject-Type-Information.html#GType"><span class="type">GType</span></a> identifier for the type is returned, otherwise the type
is newly registered, and the resulting <a href="gobject-Type-Information.html#GType"><span class="type">GType</span></a> identifier returned.
</p>
<p>
As long as any instances of the type exist, the type plugin will
not be unloaded.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>module</code></em> :</span></td>
<td> a <a href="GTypeModule.html" title="GTypeModule"><span class="type">GTypeModule</span></a>
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>name</code></em> :</span></td>
<td> name for the type
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>_static_values</code></em> :</span></td>
<td>
</td>
</tr>
<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td>
<td>the new or existing type ID
</td>
</tr>
</tbody>
</table></div>
<p>Since 2.6
</p>
</div>
</div>
<div class="refsect1" lang="en">
<a name="id2660755"></a><h2>See Also</h2>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><a href="GTypePlugin.html" title="GTypePlugin"><span class="type">GTypePlugin</span></a></span></td>
<td><p>The abstract type loader interface.</p></td>
</tr>
<tr>
<td>
<span class="term"><a
href="../glib/glib-Dynamic-Loading-of-Modules.html#GModule"
><span class="type">GModule</span></a></span></td>
<td><p>Portable mechanism for dynamically loaded modules.</p></td>
</tr>
</tbody>
</table></div>
<p>
</p>
</div>
</div>
</body>
</html>