;
; Ullrich von Bassewitz, 31.05.1998
;
; int strlen (const char* s);
;

 	.export		_strlen
	.importzp	ptr1

_strlen:
 	sta	ptr1		; Save s
 	stx	ptr1+1
 	ldx	#0		; YX used as counter
 	ldy	#0

L1:	lda	(ptr1),y
 	beq	L9
 	iny
 	bne	L1
 	inc	ptr1+1
 	inx
 	bne	L1

L9:	tya	     		; get low byte of counter, hi's all set
       	rts

