newbie needs snippet : how to obtain a string from the user in a dialog

[ronald <raalst caiway nl>]

Hi all, 

Forgive me but I am an cut& paste type cobbler. 

I am trying to make a GTK frontend for an FM tuner (included in my TV
card)
I have a working ncurses/C program and I want to exercise the brain 
by fitting it with a GTK front instead (also in C)

So far I used glade and populated the callbacks. they work nicely.
but I want to be able to "mark" frequencies with names so you can build
a list of stations. This requires a popup dialog.

I use a dialog with a gtk_entry in it. my main wonder is how to 
get the text from that entry when the user presses the OK button.
since the OK button is connected with a destroy-dialog action, 
I am confused how to get at the results of the users' effort.

all examples I can find are the "user presses button" type, 
not the "user does input". 
I have to insert my actions into that destroy chain of 
events somehow, but I dunno how.

does anybody have a C snippet handy, perhaps ? 

Thanks in advance

My code so far (please, I am only a newbie, even in C. I know it's ugly)
constructive remarks are *very* welcome 

void
on_mark_clicked                        (GtkButton       *button,
                                        gpointer         user_data)
{
 /* if freq-show = number */
 GtkWidget *entry = lookup_widget(GTK_WIDGET(button), "freq_show");
 gchar dialdata[LINEWIDTH] = "" ;
 strcpy (dialdata,gtk_entry_get_text(GTK_ENTRY(entry)));
 printf("%s",dialdata); /* DEBUG */
 gchar stnname[LINEWIDTH] = "abc" ;

 gdouble Mhznr = 0 ;
 GtkWidget *dialog  = gtk_dialog_new() ;

 char *lbltxt=" Name That Station ! ";
 GtkWidget *dg_label = gtk_label_new(lbltxt);
 GtkWidget *dg_entry = gtk_entry_new() ;
 char *bttntxt="OK";
 GtkWidget *dg_OK = gtk_button_new_with_label(bttntxt) ;

 Mhznr = getnrval ( dialdata ) ;
 if (validfreq(Mhznr))
 {  /* get station name from user with popup */
    int        text_width = LINEWIDTH; /* Width of field in characters
*/
    gtk_entry_set_width_chars(GTK_ENTRY(dg_entry), text_width);
    gtk_signal_connect_object(GTK_OBJECT (dg_OK), "clicked",
GTK_SIGNAL_FUNC(gtk_widget_destroy), GTK_OBJECT(dialog));
    gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->action_area),
dg_OK);
    gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->vbox),
dg_label);
    gtk_container_add (GTK_CONTAINER (GTK_DIALOG(dialog)->vbox),
dg_entry);
    gtk_widget_show_all (dialog);
    gtk_widget_grab_focus(dialog);

    gtk_dialog_run (GTK_DIALOG (dialog));
    strcpy(stnname,gtk_entry_get_text(GTK_ENTRY(dg_entry))) ;

    /* makestruct (freq, name) */
    /* sort-insert struct on freq */
    /* put name on freq-show (FIXME) */
    gtk_entry_set_text(GTK_ENTRY(entry),stnname);
    gtk_widget_destroy (dialog);
 }
 else