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<!-- ##### SECTION Title ##### -->
Reference Counting and Memory Mangement
<!-- ##### SECTION Short_Description ##### -->
Functions for reference counting and memory management on pixbufs.
<!-- ##### SECTION Long_Description ##### -->
<para>
#GdkPixbuf structures are reference counted. This means that an
application can share a single pixbuf among many parts of the
code. When a piece of the program needs to keep a pointer to a
pixbuf, it should add a reference to it by calling g_object_ref().
When it no longer needs the pixbuf, it should subtract a reference
by calling g_object_unref(). The pixbuf will be destroyed when
its reference count drops to zero. Newly-created #GdkPixbuf
structures start with a reference count of one.
</para>
<note>
<para>
As #GdkPixbuf is derived from #GObject now, gdk_pixbuf_ref() and
gdk_pixbuf_unref() are deprecated in favour of g_object_ref()
and g_object_unref () resp.
</para>
</note>
<para>
<emphasis>Finalizing</emphasis> a pixbuf means to free its pixel
data and to free the #GdkPixbuf structure itself. Most of the
library functions that create #GdkPixbuf structures create the
pixel data by themselves and define the way it should be freed;
you do not need to worry about those. The only function that lets
you specify how to free the pixel data is
gdk_pixbuf_new_from_data(). Since you pass it a pre-allocated
pixel buffer, you must also specify a way to free that data. This
is done with a function of type #GdkPixbufDestroyNotify. When a
pixbuf created with gdk_pixbuf_new_from_data() is finalized, your
destroy notification function will be called, and it is its
responsibility to free the pixel array.
</para>
<!-- ##### SECTION See_Also ##### -->
<para>
#GdkPixbuf, gdk_pixbuf_new_from_data().
</para>
<!-- ##### SECTION Stability_Level ##### -->
<!-- ##### SECTION Image ##### -->
<!-- ##### USER_FUNCTION GdkPixbufDestroyNotify ##### -->
<para>
A function of this type is responsible for freeing the pixel array
of a pixbuf. The gdk_pixbuf_new_from_data() function lets you
pass in a pre-allocated pixel array so that a pixbuf can be
created from it; in this case you will need to pass in a function
of #GdkPixbufDestroyNotify so that the pixel data can be freed
when the pixbuf is finalized.
</para>
@pixels: The pixel array of the pixbuf that is being finalized.
@data: User closure data.
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