--- a/NonPositionableExternalStream.st	Wed Nov 23 21:31:47 2016 +0100
+++ b/NonPositionableExternalStream.st	Thu Nov 24 10:49:28 2016 +0100
@@ -539,7 +539,12 @@
 !NonPositionableExternalStream methodsFor:'queries'!
 
 atEnd
-    "return true, if position is at end"
+    "return true, if position is at end.
+     Notice: this is a blocking operation, as we do not know in advance,
+     if there will be anything to read 
+     (i.e. if the partner will send more or close the stream).
+     If you want to check for available data, 
+     use nextAvailable:, or canReadWithoutBlocking"
 
     (self == StdInStream) ifTrue:[
         OperatingSystem hasConsole ifFalse:[