GTK 3 NoteBook closing tabs - c

Question

what I am trying to do is close tabs in a GTK notebook by a button added to the tab but the function to get the page number does not seem to work and it looks as though the pages close from the last created backwards.
void close_tab(GtkWidget *button, gpointer data){
gint pg_num = gtk_notebook_page_num(GTK_NOTEBOOK(notebook), button);
gtk_notebook_remove_page(GTK_NOTEBOOK(notebook) , pg_num);
}
void add_tab (char *name){
GtkWidget *textview = gtk_text_view_new();
GtkWidget *text = gtk_label_new(name);
GtkWidget *label = gtk_box_new(GTK_ORIENTATION_HORIZONTAL, 0);
GtkWidget *icon = gtk_image_new_from_file ("close.png");
GtkWidget *button = gtk_button_new();
gtk_button_set_image(GTK_BUTTON(button), icon);
gtk_widget_set_tooltip_text(button , "Close Tab");
gtk_box_pack_start(GTK_BOX(label), text, TRUE, TRUE, 0);
gtk_box_pack_start(GTK_BOX(label), button, FALSE, FALSE, 0);
g_signal_connect(GTK_WIDGET(button), "clicked",
G_CALLBACK(close_tab),
NULL);
GtkWidget *scrollwindow = gtk_scrolled_window_new(NULL, NULL);
gtk_container_add(GTK_CONTAINER(scrollwindow), textview);
gtk_notebook_append_page(GTK_NOTEBOOK(notebook), scrollwindow, label);
gtk_widget_show_all(label);
gtk_widget_show_all(scrollwindow);
}
void button_click(GtkWidget *button, gpointer data){
char *btn = (char *) data;
if (strcmp(btn, "New") == 0);
add_tab("new tab");
}
my experiment is with two tabs the first is made automatically with the 'text' label as "untitled", and the second as "new tab" and tried giving the button the name passed to the add tab function but the result was the same so I don't know how to make the button know what page it belongs to.

Answer 1

I figured out the solution was to pass a direct child of the page as the gpointer data, the only one that seems to work is the scrollwindow.
the remove tab function change
void close_tab(GtkWidget *button, gpointer data){
int pg_num = gtk_notebook_page_num(GTK_NOTEBOOK(notebook), data);
gtk_notebook_remove_page(GTK_NOTEBOOK(notebook) , pg_num);
}
and a change inside the add tab function
GtkWidget *scrollwindow = gtk_scrolled_window_new(NULL, NULL);
gtk_container_add(GTK_CONTAINER(scrollwindow), textview);
gtk_notebook_append_page(GTK_NOTEBOOK(notebook), scrollwindow, label);
g_signal_connect(GTK_WIDGET(button), "clicked",
G_CALLBACK(close_tab),
scrollwindow);