--- a/AbstractOperatingSystem.st	Fri Apr 29 11:47:43 2016 +0200
+++ b/AbstractOperatingSystem.st	Fri Apr 29 13:58:04 2016 +0200
@@ -1,5 +1,3 @@
-"{ Encoding: utf8 }"
-
 "
  COPYRIGHT (c) 1988 by Claus Gittinger
 	      All Rights Reserved
@@ -2370,6 +2368,8 @@
 !
 
 createFileForReadWrite:pathName
+    "open a file for reading and writing, return an os specific fileHandle."
+
     self subclassResponsibility
 !
 
@@ -2417,10 +2417,14 @@
 !
 
 openFileForAppend:pathName
+    "open a file for appending, return an os specific fileHandle."
+
     self subclassResponsibility
 !
 
 openFileForRead:pathName
+    "open a file for reading, return an os specific fileHandle."
+
     self subclassResponsibility
 !
 
@@ -2429,10 +2433,14 @@
 !
 
 openFileForReadWrite:pathName
+    "open a file for reading and writing, return an os specific fileHandle."
+
     self subclassResponsibility
 !
 
 openFileForWrite:pathName
+    "open a file for writing, return an os specific fileHandle."
+
     self subclassResponsibility
 !