--- a/OSProcess.st	Wed Feb 26 01:27:28 2020 +0100
+++ b/OSProcess.st	Wed Feb 26 01:28:43 2020 +0100
@@ -892,7 +892,6 @@
                         |data|
 
                         data := shuffledStream nextLine.
-                        "/ Transcript showCR:'got: ',data printString.
                         data notNil ifTrue:[
                             "/ Transcript showCR:'for: ',aStream printString.
                             aStream nextPutLine:data
@@ -900,6 +899,7 @@
                     ].
                 ] ifFalse:[
                     shuffledStream copyToEndInto:aStream.
+                    aStream flush.
                 ].
             ] on:WriteError do:[:ex |
                 "ignore" 
@@ -969,6 +969,8 @@
 !OSProcess methodsFor:'queries'!
 
 finishedWithSuccess
+    "return true if so"
+
     ^ exitStatus notNil and:[exitStatus success].
 !
 
@@ -997,12 +999,14 @@
      Answer true if it successfully terminated, 
      false if it could not be started or terminated with error."
 
-    ^ [
-        self startProcess
-        and:[
-            self waitUntilFinished.
-            self finishedWithSuccess.
-        ].
+    |ok|
+
+    [
+        ok := self startProcess.
+        self waitUntilFinished.
+        ok := ok & self finishedWithSuccess.
+        self waitForShufflersToFinish
+
         "if we come here, all streamsToClose have been closed 
          and all shuffler processses are terminated"
     ] ifCurtailed:[
@@ -1011,10 +1015,12 @@
         pid notNil ifTrue:[
             self terminateGroup.
         ].
+        self waitUntilFinished.
         self 
             closeHelperStreams; 
             terminateShufflerProcesses.
     ].
+    ^ ok
 
     "Modified: / 29-10-2018 / 15:59:33 / Claus Gittinger"
     "Modified: / 31-10-2018 / 12:31:42 / Maren"
@@ -1223,10 +1229,25 @@
 
 !OSProcess methodsFor:'waiting'!
 
+waitForShufflersToFinish
+    "return false if timedout; true if finished"
+
+    |processList|
+
+    "have to wait until the output shufflers shuffling command's outputs have finished their work"
+    processList := outputShufflerProcesses.
+    processList notNil ifTrue:[
+        processList do:[:eachProcess | 
+            eachProcess waitUntilTerminated.
+        ].
+        outputShufflerProcesses := nil.
+    ].
+!
+
 waitUntilFinished
     <resource: #skipInDebuggersWalkBack>
 
-    "wait with a veryy long timeout, 
+    "wait with a veeeeeery long timeout, 
      in order that ProcessorScheduler>>#checkForEndOfDispatch recognizes
      this waiting process as an user process which is still alive.
      The timeout is meant to never occur!!"
@@ -1240,29 +1261,24 @@
 !
 
 waitUntilFinishedWithTimeout:timeout
-    <resource: #skipInDebuggersWalkBack>
+    "return false if timedout; true if finished"
 
-    |processList|
+    <resource: #skipInDebuggersWalkBack>
 
     (finishSema waitWithTimeout:timeout) isNil ifTrue:[
         "timed out"
-        ^ nil.
+        ^ false.
     ].
 
     "have to wait until the output shufflers shuffling command's outputs have finished their work"
-    processList := outputShufflerProcesses.
-    processList notNil ifTrue:[
-        processList do:[:eachProcess | 
-            eachProcess waitUntilTerminated.
-        ].
-        outputShufflerProcesses := nil.
-    ].
+    self waitForShufflersToFinish.
 
     "command has finished and is no longer reading from its inputs"
     inputShufflerProcesses notNil ifTrue:[
         self terminateShufflerProcesses:inputShufflerProcesses.
         inputShufflerProcesses := nil.
     ].
+    ^ true
 
     "Modified: / 30-05-2018 / 13:57:39 / Claus Gittinger"
     "Modified: / 01-11-2018 / 15:53:09 / Stefan Vogel"