glib/docs/reference/gobject/tmpl/gclosure.sgml

<!-- ##### SECTION Title ##### -->
Closures

<!-- ##### SECTION Short_Description ##### -->
Functions as first-class objects

<!-- ##### SECTION Long_Description ##### -->
<para>

</para>

<!-- ##### SECTION See_Also ##### -->
<para>

</para>

<!-- ##### MACRO G_CLOSURE_NEEDS_MARSHAL ##### -->
<para>

</para>

@closure: 


<!-- ##### MACRO G_CLOSURE_N_NOTIFIERS ##### -->
<para>

</para>

@cl: 


<!-- ##### MACRO G_CCLOSURE_SWAP_DATA ##### -->
<para>

</para>

@cclosure: 


<!-- ##### MACRO G_CALLBACK ##### -->
<para>

</para>

@f: 


<!-- ##### USER_FUNCTION GCallback ##### -->
<para>

</para>



<!-- ##### STRUCT GClosure ##### -->
<para>

</para>

@in_marshal: 
@is_invalid: Indicates whether the closure has been invalidated by g_closure_invalidate()

<!-- ##### MACRO G_TYPE_CLOSURE ##### -->
<para>
The #GType for #GClosure.
</para>



<!-- ##### STRUCT GCClosure ##### -->
<para>

</para>

@closure: 
@callback: 

<!-- ##### USER_FUNCTION GClosureMarshal ##### -->
<para>

</para>

@closure: 
@return_value: 
@n_param_values: 
@param_values: 
@invocation_hint: 
@marshal_data: 


<!-- ##### USER_FUNCTION GClosureNotify ##### -->
<para>

</para>

@data: 
@closure: 


<!-- ##### STRUCT GClosureNotifyData ##### -->
<para>

</para>

@data: 
@notify: 

<!-- ##### FUNCTION g_cclosure_new ##### -->
<para>

</para>

@callback_func: 
@user_data: 
@destroy_data: 
@Returns: 


<!-- ##### FUNCTION g_cclosure_new_swap ##### -->
<para>

</para>

@callback_func: 
@user_data: 
@destroy_data: 
@Returns: 


<!-- ##### FUNCTION g_cclosure_new_object ##### -->
<para>

</para>

@callback_func: 
@object: 
@Returns: 


<!-- ##### FUNCTION g_cclosure_new_object_swap ##### -->
<para>

</para>

@callback_func: 
@object: 
@Returns: 


<!-- ##### FUNCTION g_closure_new_object ##### -->
<para>

</para>

@sizeof_closure: 
@object: 
@Returns: 


<!-- ##### FUNCTION g_closure_ref ##### -->
<para>
Increment the reference count on a closure to force it staying
alive while the caller holds a pointer to it.
</para>

@closure: #GClosure to increment the reference count on
@Returns: The @closure passed in, for convenience


<!-- ##### FUNCTION g_closure_sink ##### -->
<para>
Take over the initial ownership of a closure.
When closures are newly created, they get an initial reference count
of 1, eventhough no caller has yet invoked g_closure_ref() on the @closure.
Code entities that store closures for notification purposes are supposed
to call this function, for example like this:
<informalexample><programlisting>
static GClosure *notify_closure = NULL;
void
foo_notify_set_closure (GClosure *closure)
{
  if (notify_closure)
    g_closure_unref (notify_closure);
  notify_closure = closure;
  if (notify_closure)
    {
      g_closure_ref (notify_closure);
      g_closure_sink (notify_closure);
    }
}
</programlisting></informalexample>
Because g_closure_sink() may decrement the reference count of a closure
(if it hasn't been called on @closure yet) just like g_closure_unref(),
g_closure_ref() should be called prior to this function.
</para>

@closure: #GClosure to decrement the initial reference count on, if it's
          still being held


<!-- ##### FUNCTION g_closure_unref ##### -->
<para>
Decrement the reference count of a closure after it was
previously incremented by the same caller. The closure
will most likely be destroyed and freed after this function
returns.
</para>

@closure: #GClosure to decrement the reference count on


<!-- ##### FUNCTION g_closure_invoke ##### -->
<para>

</para>

@closure: 
@return_value: 
@n_param_values: 
@param_values: 
@invocation_hint: 


<!-- ##### FUNCTION g_closure_invalidate ##### -->
<para>
This function sets a flag on the closure to indicate that it's
calling environment has become invalid, and thus causes any future
invocations of g_closure_invoke() on this @closure to be ignored.
Also, invalidation notifiers installed on the closure will be called
at this point, and since invalidation notifiers may unreference
the closure, @closure should be considered an invalidated pointer
atfer this function, unles g_closure_ref() was called beforehand.
</para>

@closure: GClosure to invalidate


<!-- ##### FUNCTION g_closure_add_finalize_notifier ##### -->
<para>

</para>

@closure: 
@notify_data: 
@notify_func: 


<!-- ##### FUNCTION g_closure_add_invalidate_notifier ##### -->
<para>

</para>

@closure: 
@notify_data: 
@notify_func: 


<!-- ##### FUNCTION g_closure_remove_finalize_notifier ##### -->
<para>

</para>

@closure: 
@notify_data: 
@notify_func: 


<!-- ##### FUNCTION g_closure_remove_invalidate_notifier ##### -->
<para>

</para>

@closure: 
@notify_data: 
@notify_func: 


<!-- ##### FUNCTION g_closure_new_simple ##### -->
<para>

</para>

@sizeof_closure: 
@data: 
@Returns: 


<!-- ##### FUNCTION g_closure_set_marshal ##### -->
<para>

</para>

@closure: 
@marshal: 


<!-- ##### FUNCTION g_closure_add_marshal_guards ##### -->
<para>

</para>

@closure: 
@pre_marshal_data: 
@pre_marshal_notify: 
@post_marshal_data: 
@post_marshal_notify: 


<!-- ##### FUNCTION g_closure_set_meta_marshal ##### -->
<para>

</para>

@closure: 
@marshal_data: 
@meta_marshal: 


<!-- ##### FUNCTION g_source_set_closure ##### -->
<para>
Set the callback for a source as a #GClosure.
</para>
<para>
If the source is not one of the standard GLib types, the @closure_callback
and @closure_marshal fields of the GSourceFuncs structure must have been
filled in with pointers to appropriate functions.
</para>

@source: the source
@closure: a #GClosure


<!-- ##### MACRO G_TYPE_IO_CHANNEL ##### -->
<para>
The #GType for #GIOChannel.
</para>



<!-- ##### MACRO G_TYPE_IO_CONDITION ##### -->
<para>
The #GType for #GIOCondition.
</para>