diff --git a/libsrc/apple2/close.s b/libsrc/apple2/close.s
index 45c345211..18c4a14dd 100644
--- a/libsrc/apple2/close.s
+++ b/libsrc/apple2/close.s
@@ -7,7 +7,6 @@
         .export 	_close
 
         .import		closedirect, freebuffer
-        .import 	return0
 
         .include	"errno.inc"
         .include	"filedes.inc"
@@ -32,10 +31,10 @@ zerofd: lda	#$00
         jsr	freebuffer
 
         ; Return success
-        jmp	return0
-
-        ; Set __errno
-errno:  jmp	__directerrno
+        lda	#$00
 
         ; Set __oserror
 oserr:  jmp	__mappederrno
+
+        ; Set __errno
+errno:  jmp	__directerrno
diff --git a/libsrc/apple2/open.s b/libsrc/apple2/open.s
index 9d3c158b6..de0bb63fa 100644
--- a/libsrc/apple2/open.s
+++ b/libsrc/apple2/open.s
@@ -199,6 +199,7 @@ done:   lda	tmp1		; Restore fd
 
         ; Return success
         ldx	#$00
+        stx	__oserror
         rts
 
 freebuffer:
diff --git a/libsrc/apple2/read.s b/libsrc/apple2/read.s
index d85000730..dccde611f 100644
--- a/libsrc/apple2/read.s
+++ b/libsrc/apple2/read.s
@@ -47,8 +47,11 @@ _read:
         ldy	#READ_CALL
         jmp	rwcommon
 
-        ; Set counter to zero
+        ; Device succeeds always
 device: lda	#$00
+        sta	__oserror
+
+        ; Set counter to zero
         sta	ptr3
         sta	ptr3+1
 
diff --git a/libsrc/apple2/rootdir.s b/libsrc/apple2/rootdir.s
index e2134e5d4..77d986aae 100644
--- a/libsrc/apple2/rootdir.s
+++ b/libsrc/apple2/rootdir.s
@@ -46,9 +46,7 @@ _rootdir:
         lda	#$00
         sta	(ptr1),y
         
-        ; Return success
-        tax
-        rts
+        ; Return success	; A = 0
         
         ; Set __oserror
 oserr:  jmp	__mappederrno
diff --git a/libsrc/apple2/rwcommon.s b/libsrc/apple2/rwcommon.s
index b9f86dff3..c1e78c503 100644
--- a/libsrc/apple2/rwcommon.s
+++ b/libsrc/apple2/rwcommon.s
@@ -51,6 +51,7 @@ rwcommon:
 
 rwepilog:
         ; Return success
+        sta	__oserror	; A = 0
         lda	mliparam + MLI::RW::TRANS_COUNT
         ldx	mliparam + MLI::RW::TRANS_COUNT+1
         rts
diff --git a/libsrc/apple2/write.s b/libsrc/apple2/write.s
index ec9efa3b7..d8f7fcd84 100644
--- a/libsrc/apple2/write.s
+++ b/libsrc/apple2/write.s
@@ -100,7 +100,8 @@ output: jsr	COUT		; Preserves X and Y
         bpl	next
 
         ; Return success
-done:   jmp	rwepilog
+done:   lda	#$00
+        jmp	rwepilog
 
         ; Load errno code
 einval: lda	#EINVAL