diff --git a/repository/Grease-Squeak6-Core.package/GRSqueakPlatform.class/instance/writeFileStreamOn.do.binary..st b/repository/Grease-Squeak6-Core.package/GRSqueakPlatform.class/instance/writeFileStreamOn.do.binary..st
new file mode 100644
index 00000000..1207150a
--- /dev/null
+++ b/repository/Grease-Squeak6-Core.package/GRSqueakPlatform.class/instance/writeFileStreamOn.do.binary..st
@@ -0,0 +1,8 @@
+as yet unclassified
+writeFileStreamOn: aString do: aBlock binary: aBoolean 
+	| stream |
+	stream := aBoolean
+				ifTrue: [ (MultiByteFileStream fileNamed: aString) ascii; wantsLineEndConversion: true; yourself ]
+				ifFalse: [ (FileStream fileNamed: aString) binary ].
+	[ aBlock value: stream ]
+		ensure: [ stream close ]
\ No newline at end of file