--- a/AbstractOperatingSystem.st	Thu Feb 11 15:42:08 2016 +0100
+++ b/AbstractOperatingSystem.st	Thu Feb 11 15:46:36 2016 +0100
@@ -1,3 +1,5 @@
+"{ Encoding: utf8 }"
+
 "
  COPYRIGHT (c) 1988 by Claus Gittinger
 	      All Rights Reserved
@@ -3264,6 +3266,18 @@
 %}
 !
 
+interruptProcess:processId
+    "interrupt an OS process (CTRL-C)."
+
+    self subclassResponsibility
+!
+
+interruptProcessGroup:processGroupId
+    "interrupt an OS process group (CTRL-C)."
+
+    self subclassResponsibility
+!
+
 interruptsBlocked
     "return true, if interrupt handling is currently disabled;
      false otherwise."
@@ -3391,6 +3405,15 @@
     self subclassResponsibility
 !
 
+sendSignal:signalNumber to:processId toGroup:toGroupBoolean toAll:toAllBoolean
+    "send a unix signal to some process (maybe myself).
+     Returns false if any error occurred, true otherwise.
+
+     Do not confuse UNIX signals with Smalltalk-Signals."
+
+    self subclassResponsibility
+!
+
 startSpyTimer
     "trigger a spyInterrupt, to be signalled after some short (virtual) time.
      Return true, if the spy-timerInterrupt was enabled.