When is g_object_ref needed ?

[Frédéric Terraza <fterraza free fr>]

Hello,

I must use g_object_unref  to free a gdk or a gtk object. There are lots 
of deprecated functions that are now replaced by g_object_unref (such as 
g_pixmap_unref,  gdk_gc_unref).

But must I use g_object_ref after the creation of a pixmap or a gc, 
since there used to be g_pixmap_ref and g_gc_ref functions ?