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; strlen() implementation that only looks at the first 256
; byte of the string. returns 255 if the length is >=255.
; saves a measly 4 bytes over the cc65 strlen().
; extern unsigned char strlen8(const char *str);
.importzp ptr1
.export _strlen8
_strlen8:
sta ptr1
stx ptr1+1
ldy #0
@loop:
lda (ptr1),y
beq @done
iny
bne @loop
dey ; return(255) if Y rolls over
@done:
tya
ldx #0 ; sadly necessary even though we return a char...
rts
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