GTK newbie help on G_CALLBACK

[Rudra Banerjee <bnrj rudra gmail com>]

Dear Friends,
I have taken a project (my own, not homework) to develop a table. I
generally work with fortran, don't know C that much.
What I want is a gtk clist to pop up when I press a button, via
callback. The button widget in my code is


/* Create first button */
    button = gtk_button_new_with_label ("B1");

    /* When the button is clicked, we call the "callback" function
     * with a pointer to "button 1" as its argument */
    g_signal_connect (button, "clicked",
                  G_CALLBACK (callback), (gpointer) "B1");


    /* Insert button 1 into the upper left quadrant of the table */
    gtk_table_attach_defaults (GTK_TABLE (table), button, 0, 1, 0, 1);

    gtk_widget_show (button);
The definations are mostly based on
http://developer.gnome.org/gtk-tutorial/2.24/x344.html

What I want to do is callback to execute another gtk file, rather than
what shown in the example. The source code of the pop up gtk file is:
http://www.gtk.org/tutorial1.2/gtk_tut.html#toc11.10


Please help me.