diff -r c23daa6996c2 -r 22e65b8e20f4 targets/Win32/plc_Win32_main.c
--- a/targets/Win32/plc_Win32_main.c	Tue Mar 24 17:33:46 2009 +0100
+++ b/targets/Win32/plc_Win32_main.c	Mon Mar 30 17:04:30 2009 +0200
@@ -1,6 +1,6 @@
 /**
  * Win32 specific code
- **/ 
+ **/
 
 #include <stdio.h>
 #include <sys/timeb.h>
@@ -19,7 +19,7 @@
 void PLC_GetTime(IEC_TIME *CURRENT_TIME)
 {
 	_ftime(&timetmp);
-	
+
 	(*CURRENT_TIME).tv_sec = timetmp.time;
 	(*CURRENT_TIME).tv_nsec = timetmp.millitm * 1000000;
 }
@@ -36,11 +36,11 @@
 	LARGE_INTEGER liDueTime;
 	/* arg 2 of SetWaitableTimer take 100 ns interval*/
 	liDueTime.QuadPart =  next / (-100);
-	
+
 	/*
 	printf("SetTimer(%lld,%lld)\n",next, period);
 	*/
-	
+
 	if (!SetWaitableTimer(PLC_timer, &liDueTime, common_ticktime__, NULL, NULL, 0))
     {
         printf("SetWaitableTimer failed (%d)\n", GetLastError());
@@ -66,9 +66,9 @@
 
 HANDLE PLC_thread;
 HANDLE debug_sem;
-HANDLE debug_wait_sem; 
+HANDLE debug_wait_sem;
 HANDLE python_sem;
-HANDLE python_wait_sem; 
+HANDLE python_wait_sem;
 
 #define maxval(a,b) ((a>b)?a:b)
 int startPLC(int argc,char **argv)
@@ -77,54 +77,54 @@
 	/* Translate PLC's microseconds to Ttick nanoseconds */
 	Ttick = 1000000 * maxval(common_ticktime__,1);
 
-	debug_sem = CreateSemaphore( 
+	debug_sem = CreateSemaphore(
 							NULL,           // default security attributes
 					        1,  			// initial count
 					        1,  			// maximum count
 					        NULL);          // unnamed semaphore
-    if (debug_sem == NULL) 
+    if (debug_sem == NULL)
     {
         printf("startPLC CreateSemaphore debug_sem error: %d\n", GetLastError());
         return;
     }
-    
-	debug_wait_sem = CreateSemaphore( 
+
+	debug_wait_sem = CreateSemaphore(
 					        NULL,           // default security attributes
 					        0,  			// initial count
 					        1,  			// maximum count
 					        NULL);          // unnamed semaphore
 
-    if (debug_wait_sem == NULL) 
+    if (debug_wait_sem == NULL)
     {
         printf("startPLC CreateSemaphore debug_wait_sem error: %d\n", GetLastError());
         return;
     }
 
-	python_sem = CreateSemaphore( 
+	python_sem = CreateSemaphore(
 					        NULL,           // default security attributes
 					        1,  			// initial count
 					        1,  			// maximum count
 					        NULL);          // unnamed semaphore
 
-    if (python_sem == NULL) 
+    if (python_sem == NULL)
     {
         printf("startPLC CreateSemaphore python_sem error: %d\n", GetLastError());
         return;
     }
-	python_wait_sem = CreateSemaphore( 
+	python_wait_sem = CreateSemaphore(
 					        NULL,           // default security attributes
 					        0,  			// initial count
 					        1,  			// maximum count
 					        NULL);          // unnamed semaphore
 
 
-    if (python_wait_sem == NULL) 
+    if (python_wait_sem == NULL)
     {
         printf("startPLC CreateSemaphore python_wait_sem error: %d\n", GetLastError());
         return;
     }
 
-	
+
 	/* Create a waitable timer */
     PLC_timer = CreateWaitableTimer(NULL, FALSE, "WaitableTimer");
     if(NULL == PLC_timer)
@@ -172,10 +172,10 @@
 /* from plc_debugger.c */
 int WaitDebugData()
 {
-	WaitForSingleObject(debug_wait_sem, INFINITE);
+	if(WaitForSingleObject(debug_wait_sem, INFINITE) != WAIT_OBJECT_0) return -1;
 	return __debug_tick;
 }
- 
+
 /* Called by PLC thread when debug_publish finished
  * This is supposed to unlock debugger thread in WaitDebugData*/
 void InitiateDebugTransfer()
@@ -190,7 +190,7 @@
 {
 	__DEBUG = 0;
     /* Prevent PLC to enter debug code */
-	WaitForSingleObject(debug_sem, INFINITE);  
+	WaitForSingleObject(debug_sem, INFINITE);
 }
 
 void resumeDebug()
@@ -204,9 +204,9 @@
 int WaitPythonCommands(void)
 {
     /* Wait signal from PLC thread */
-	WaitForSingleObject(python_wait_sem, INFINITE);
-}
- 
+	return WaitForSingleObject(python_wait_sem, INFINITE);
+}
+
 /* Called by PLC thread on each new python command*/
 void UnBlockPythonCommands(void)
 {