Index: trunk/src/event.h
===================================================================
--- trunk/src/event.h	(revision 20454)
+++ trunk/src/event.h	(revision 20455)
@@ -46,6 +46,8 @@
 	PCB_EVENT_LIBRARY_CHANGED,        /* called after a change in the footprint lib (used to be the LibraryChanged action) */
 	PCB_EVENT_FONT_CHANGED,           /* called when a font has changed; argument is the font ID */
 
+	PCB_EVENT_UNDO_POST,              /* called after an undo/redo operation; argument is an integer pcb_undo_ev_t */
+
 	PCB_EVENT_NEW_PSTK,               /* called when a new padstack is created */
 
 	PCB_EVENT_BUSY,                   /* called before CPU-intensive task begins */
Index: trunk/src/undo.c
===================================================================
--- trunk/src/undo.c	(revision 20454)
+++ trunk/src/undo.c	(revision 20455)
@@ -52,6 +52,7 @@
 #include "data.h"
 #include "draw.h"
 #include "error.h"
+#include "event.h"
 #include "insert.h"
 #include "polygon.h"
 #include "remove.h"
@@ -119,6 +120,8 @@
 	else if (pcb_undo_and_draw)
 		pcb_draw();
 
+	pcb_event(PCB_EVENT_UNDO_POST, "i", PCB_UNDO_EV_UNDO);
+
 	return res;
 }
 
@@ -161,6 +164,8 @@
 	else if (pcb_undo_and_draw)
 		pcb_draw();
 
+	pcb_event(PCB_EVENT_UNDO_POST, "i", PCB_UNDO_EV_REDO);
+
 	return res;
 }
 
@@ -210,8 +215,10 @@
  */
 void pcb_undo_clear_list(pcb_bool Force)
 {
-	if (pcb_uundo.num_undo && (Force || pcb_gui->confirm_dialog("OK to clear 'undo' buffer?", 0)))
+	if (pcb_uundo.num_undo && (Force || pcb_gui->confirm_dialog("OK to clear 'undo' buffer?", 0))) {
 		uundo_list_clear(&pcb_uundo);
+		pcb_event(PCB_EVENT_UNDO_POST, "i", PCB_UNDO_EV_CLEAR_LIST);
+	}
 }
 
 /* ---------------------------------------------------------------------------
@@ -247,6 +254,7 @@
 void pcb_undo_truncate_from(uundo_serial_t sfirst)
 {
 	uundo_list_truncate_from(&pcb_uundo, sfirst);
+	pcb_event(PCB_EVENT_UNDO_POST, "i", PCB_UNDO_EV_TRUNCATE);
 }
 
 int undo_check(void)
Index: trunk/src/undo.h
===================================================================
--- trunk/src/undo.h	(revision 20454)
+++ trunk/src/undo.h	(revision 20455)
@@ -35,6 +35,13 @@
 /* Temporary for compatibility */
 #include "undo_old.h"
 
+typedef enum pcb_undo_ev_e {
+	PCB_UNDO_EV_UNDO,
+	PCB_UNDO_EV_REDO,
+	PCB_UNDO_EV_CLEAR_LIST,
+	PCB_UNDO_EV_TRUNCATE
+} pcb_undo_ev_t;
+
 void *pcb_undo_alloc(pcb_board_t *pcb, const uundo_oper_t *oper, size_t data_len);
 int pcb_undo(pcb_bool);
 int pcb_redo(pcb_bool);