--- a/AbstractOperatingSystem.st	Thu Apr 16 16:57:05 2020 +0200
+++ b/AbstractOperatingSystem.st	Fri Apr 17 09:46:35 2020 +0200
@@ -17,8 +17,8 @@
 
 Object subclass:#AbstractOperatingSystem
 	instanceVariableNames:''
-	classVariableNames:'ConcreteClass MyPid DefaultVoice ErrorSignal LastErrorNumber
-		LocaleInfo OSSignals PipeFailed Resources VoiceMapping
+	classVariableNames:'ConcreteClass MyPid ErrorSignal LastErrorNumber LocaleInfo
+		OSSignals PipeFailed Resources VoiceMapping DefaultVoice
 		BestVoiceForLanguageMapping ConsoleOutputEncoder'
 	poolDictionaries:''
 	category:'System-Support'
@@ -250,6 +250,12 @@
 
 initializeConcreteClass
     OperatingSystem := ConcreteClass := self getConcreteClass.
+!
+
+reinitialize
+    MyPid := nil.   "/ the cached pid is no longer valid after restart
+
+    "Created: / 17-04-2020 / 09:46:15 / Stefan Vogel"
 ! !
 
 !AbstractOperatingSystem class methodsFor:'OS signal constants'!