--- a/Monitor.st	Fri Jul 05 18:01:41 1996 +0200
+++ b/Monitor.st	Sat Jul 06 23:54:52 1996 +0200
@@ -153,6 +153,11 @@
 
     |thisProcess|
 
+    count == 0 ifTrue:[
+        'MONITOR: already left' errorPrintCR.
+        ^ self
+    ].
+
     thisProcess := Processor activeProcess.
 
     "
@@ -171,7 +176,7 @@
     owningProcess := nil.
     sema signal.
 
-    "Modified: 3.5.1996 / 17:25:57 / cg"
+    "Modified: 6.7.1996 / 22:30:47 / cg"
 ! !
 
 !Monitor methodsFor:'initialization'!
@@ -208,5 +213,5 @@
 !Monitor  class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic2/Monitor.st,v 1.4 1996-06-27 15:54:25 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic2/Monitor.st,v 1.5 1996-07-06 21:54:52 cg Exp $'
 ! !