Using g_signal_connect in an event handler

[Lorenzo Marcon <lorenzo marcon startrekitalia com>]

Hi to all,
this is my first experience with GTK+ and my first post here too.
I'm currently writing a small application using GtkNotebook. (Not multi-thread 
or multi-process)

My application works in this way:
- The main function draws the main GUI and associate some event handlers to 
some buttons
- When one of this button is clicked, the event hanlder associated with it 
creates a new tab in the GtkNotebook.
- Every created tab has an xpm image in the label that allows to close it. To 
do this I have to connect the event_box containing the xpm image with the 
"close-tab" event handler.

So I have to use the "g_signal_connect" function again in the event handler 
called by the button pressure. The problem is that I do not seem able to pass 
correctly arguments in this second call.

int main(int argc, char *argv[]) {
        ...
        gpointer data[5];
        ...
        data[0] = (gpointer) gtk_entry_get_text (GTK_ENTRY (entry));
        data[1] = (gpointer) notebook;
        data[2] = (gpointer) progress_bar;
        data[3] = (gpointer) &stop;
        data[4] = (gpointer) window;
        ...
        g_signal_connect (G_OBJECT (button), "clicked", G_CALLBACK (enter_callback), 
data);
        ...
}
        
gboolean enter_callback(GtkWidget *widget, gpointer *data) {
        ...
        g_signal_connect (G_OBJECT (event_box), "button-press-event", G_CALLBACK 
(x_click_callback), data[1]);
        ....
}

gboolean x_click_callback(GtkWidget *event_box, gpointer data) {
        //Here I get segfault if I try to remove the tab.
}

I have tried to print out the value of the pointer to the Gtknotebook with a 
simple g_print("%p", notebook) both in the enter callback and 
x_click_callback. They are always different.
I cannot explain this to myself, because I'm successfully passing arguments 
and resolving them in the first event handler.

Any help will be appreciated. Thank you.