LinuxQuestions.org - GtkFileChooserDialog: How to select both, files and directories?

hi there!

first of all: I am all new to gtk2 and currently working on my first gui project.

now what I want to do is being able to use a GtkFileChooserDialog in order to select both(!), files and directories.
is this possilbe? if yes - how?
by now, I have only succeeded in selecting either files or directories...

Code:

GtkWidget *chooser;

chooser = gtk_file_chooser_dialog_new ("Add Files",

                                        NULL,

                                        GTK_FILE_CHOOSER_ACTION_OPEN, /* or GTK_FILE_CHOOSER_ACTION_SELECT_FOLDER */

                                        GTK_STOCK_CANCEL, GTK_RESPONSE_CANCEL,

                                        GTK_STOCK_OPEN, GTK_RESPONSE_ACCEPT,

                                        NULL);

gtk_file_chooser_set_select_multiple (GTK_FILE_CHOOSER (chooser), TRUE);

many thanks in advance

froedi