--- a/OSProcess.st	Tue May 22 12:24:27 2018 +0200
+++ b/OSProcess.st	Tue May 22 12:43:11 2018 +0200
@@ -1,21 +1,23 @@
+"{ Encoding: utf8 }"
+
 "{ Package: 'stx:libbasic' }"
 
 "{ NameSpace: Smalltalk }"
 
 Object subclass:#OSProcess
-        instanceVariableNames:'pid command environment directory inStream outStream errorStream
-                auxStream showWindow lineWise newPgrp exitStatus finishSema
-                shufflerProcesses streamsToClose terminateActionBlock'
-        classVariableNames:''
-        poolDictionaries:''
-        category:'System-Support'
+	instanceVariableNames:'pid command environment directory inStream outStream errorStream
+		auxStream showWindow lineWise newPgrp exitStatus finishSema
+		shufflerProcesses streamsToClose terminateActionBlock'
+	classVariableNames:''
+	poolDictionaries:''
+	category:'System-Support'
 !
 
 OSProcess subclass:#RemoteOSProcess
-        instanceVariableNames:'host'
-        classVariableNames:'MethodPerHost'
-        poolDictionaries:''
-        privateIn:OSProcess
+	instanceVariableNames:'host'
+	classVariableNames:'MethodPerHost'
+	poolDictionaries:''
+	privateIn:OSProcess
 !
 
 !OSProcess class methodsFor:'documentation'!
@@ -59,10 +61,11 @@
   send command's output to the Transcript:
                                                             [exBegin]
     OSProcess new 
-        command:'ls -l';
+        terminateActionBlock:[:status | Transcript showCR:status. Transcript showCR:status isError];
+        command:'lsxxxx -l';
         outStream:Transcript;
         lineWise:true;
-        execute.
+        startProcess.
                                                             [exEnd]
 
   send command's output to my stdout (see console):
@@ -476,11 +479,16 @@
 terminateActionBlock:aBlock
     "set the callback block,
      that will be called when the command has finished or was terminated.
-     If non-nil, it will be called with optional argument:status and:self, the OSProcess."
+     If non-nil, it will be called with optional argument:status and:self, the OSProcess.
+     WARNING: 
+        if the active-process calling #startProcess is already dead (i.e. terminated),
+        this callback will be called by the scheduler;
+        otherwise, the calling process will be interrupted to perform this callback.
+        Therefore: do not open any GUI or other blocking actions in it."
 
     terminateActionBlock := aBlock.
 
-    "Modified (comment): / 22-05-2018 / 12:21:12 / Claus Gittinger"
+    "Modified (comment): / 22-05-2018 / 12:42:21 / Claus Gittinger"
 ! !
 
 !OSProcess methodsFor:'initialization'!
@@ -683,7 +691,7 @@
      Answer true if the command could be started, false if not.
      Return immediately (do not wait until the command is finished)." 
 
-    |externalInStream externalAuxStream externalErrorStream externalOutStream|
+    |externalInStream externalAuxStream externalErrorStream externalOutStream callingProcess|
 
     shufflerProcesses := OrderedCollection new:4.
     streamsToClose := OrderedCollection new:2.
@@ -705,6 +713,8 @@
     UserPreferences current logExecutedOSCommands ifTrue:[
         Transcript showCR:('OS command: ',self startCommand printString).  
     ].
+
+    callingProcess := Processor activeProcess.
     
     Processor 
         monitor:[
@@ -733,7 +743,14 @@
                 
                 finishSema signal.
                 terminateActionBlock notNil ifTrue:[
-                    terminateActionBlock valueWithOptionalArgument:status and:self.
+                    callingProcess isDead ifTrue:[    
+                        terminateActionBlock valueWithOptionalArgument:status and:self.
+                    ] ifFalse:[
+                        callingProcess 
+                            interruptWith:[
+                                terminateActionBlock valueWithOptionalArgument:status and:self.
+                            ]        
+                    ].    
                 ].
             ].
         ].
@@ -755,7 +772,7 @@
 
     ^ true.
 
-    "Modified: / 22-05-2018 / 12:23:48 / Claus Gittinger"
+    "Modified: / 22-05-2018 / 12:39:18 / Claus Gittinger"
 ! !
 
 !OSProcess methodsFor:'terminating'!