add: return FALSE;
context: void selection_ligne_categ ( GtkCTree *arbre_categ,			     GtkCTreeNode *noeud,			     gint colonne,			     gpointer null ){  GtkCTreeNode *node_tmp;  node_tmp = noeud;  while ( GTK_CTREE_ROW ( node_tmp ) -> level  != 1 )    node_tmp = GTK_CTREE_ROW ( node_tmp ) -> parent;  if ( GTK_CTREE_ROW ( noeud ) -> level != 1 )    gtk_widget_set_sensitive ( bouton_ajouter_sous_categorie,			       FALSE );  else    gtk_widget_set_sensitive ( bouton_ajouter_sous_categorie,			       TRUE );  if ( GTK_CTREE_ROW ( noeud ) -> level  == 1       &&       gtk_ctree_node_get_row_data ( GTK_CTREE ( arbre_categ ),				     noeud ))    {      struct struct_categ *categ;        categ = gtk_ctree_node_get_row_data ( GTK_CTREE ( arbre_categ ),					    noeud );      gtk_signal_handler_block_by_func ( GTK_OBJECT ( entree_nom_categ ),					 GTK_SIGNAL_FUNC ( modification_du_texte_categ),					 NULL );      gtk_entry_set_text ( GTK_ENTRY ( entree_nom_categ ),			   categ -> nom_categ );      gtk_signal_handler_unblock_by_func ( GTK_OBJECT ( entree_nom_categ ),					   GTK_SIGNAL_FUNC ( modification_du_texte_categ),					   NULL );      gtk_object_set_data ( GTK_OBJECT ( entree_nom_categ ),			    "adr_struct_categ",			    categ );      gtk_object_set_data ( GTK_OBJECT ( entree_nom_categ ),			    "adr_struct_sous_categ",			    NULL );      gtk_widget_set_sensitive ( bouton_supprimer_categ,				 TRUE );      gtk_widget_set_sensitive ( entree_nom_categ,				 TRUE );      gtk_widget_set_sensitive ( bouton_categ_debit,				 TRUE );      gtk_widget_set_sensitive ( bouton_categ_credit,				 TRUE );      gtk_signal_handler_block_by_func ( GTK_OBJECT ( bouton_categ_debit ),					 GTK_SIGNAL_FUNC ( modification_du_texte_categ ),					 NULL );      if ( categ -> type_categ )	gtk_toggle_button_set_active ( GTK_TOGGLE_BUTTON ( bouton_categ_debit ),				       TRUE );      else	gtk_toggle_button_set_active ( GTK_TOGGLE_BUTTON ( bouton_categ_credit ),				       TRUE );      gtk_signal_handler_unblock_by_func ( GTK_OBJECT ( bouton_categ_debit ),					   GTK_SIGNAL_FUNC ( modification_du_texte_categ ),					   NULL );    }  else    if ( GTK_CTREE_ROW ( noeud ) -> level  == 2	 &&	 gtk_ctree_node_get_row_data ( GTK_CTREE ( arbre_categ ),				       noeud )	 &&	 gtk_ctree_node_get_row_data ( GTK_CTREE ( arbre_categ ),				       GTK_CTREE_ROW ( noeud ) -> parent ))    {      struct struct_sous_categ *sous_categ;      sous_categ = gtk_ctree_node_get_row_data ( GTK_CTREE ( arbre_categ ),						 noeud );      gtk_signal_handler_block_by_func ( GTK_OBJECT ( entree_nom_categ ),					 GTK_SIGNAL_FUNC ( modification_du_texte_categ),					 NULL );      gtk_entry_set_text ( GTK_ENTRY ( entree_nom_categ ),			   sous_categ -> nom_sous_categ );      gtk_signal_handler_unblock_by_func ( GTK_OBJECT ( entree_nom_categ ),					   GTK_SIGNAL_FUNC ( modification_du_texte_categ),					   NULL );      gtk_object_set_data ( GTK_OBJECT ( entree_nom_categ ),			    "adr_struct_categ",			    NULL );      gtk_object_set_data ( GTK_OBJECT ( entree_nom_categ ),			    "adr_struct_sous_categ",			    sous_categ );      gtk_widget_set_sensitive ( bouton_supprimer_categ,				 TRUE );      gtk_widget_set_sensitive ( entree_nom_categ,				 TRUE );    }}