diff --git a/libsrc/apple2/initcwd.s b/libsrc/apple2/initcwd.s
index c17e081e3..77aa1442f 100644
--- a/libsrc/apple2/initcwd.s
+++ b/libsrc/apple2/initcwd.s
@@ -4,16 +4,21 @@
 
         .export         initcwd
         .import		__cwd
+        .import		subysp, addysp
 
         .include	"zeropage.inc"
         .include        "mli.inc"
 
-        .segment        "INIT"
-        
+        .segment	"INIT"
+
 initcwd:
-        ; Use imported buffer
-        lda	#<__cwd
-        ldx	#>__cwd
+        ; Alloc prefix buffer
+        ldy	#1 + 64+1	; Length byte + max pathname length+trailing slash
+        jsr	subysp
+
+        ; Use allocated prefix buffer
+        lda	sp
+        ldx	sp+1
         sta     mliparam + MLI::PREFIX::PATHNAME
         stx     mliparam + MLI::PREFIX::PATHNAME+1
 
@@ -21,19 +26,24 @@ initcwd:
         lda     #GET_PREFIX_CALL
         ldx     #PREFIX_COUNT
         jsr     callmli
+        bcs	done
 
-        ; Check length byte
-        ldx	__cwd
+        ; Check for null prefix
+        ldy	#$00
+        lda	(sp),y
         beq	done
 
-        ; Replace trailing slash with zero
-        sta	__cwd,x		; A = 0
-
-        ; Remove length byte
-        tax
-:       inx
-        lda	__cwd,x
-        sta	__cwd-1,x
+        ; Set current working directory
+        ; - omit trailing slash and length byte
+        ; - terminating zero already in place
+        tay
+        dey
+:       lda	(sp),y
+        sta	__cwd-1,y
+        dey
         bne	:-
 
-done:   rts
+        ; Cleanup stack
+done:   ldy	#1 + 64+1	; Length byte + max pathname length+trailing slash
+        jmp     addysp
+