forg: iny ; Increment offset. lda buf, y jsr iswhite bcs forg ; Reset y, if we hit the null terminator. cmp #$2E ; Is this character a '.'? bne forg_exit ; No, so return. sty org ; Yes, so store the origin. forg_end: iny ; Increment offset. lda buf, y jsr istoken bcs forg_end dey sty scr_col forg_exit: rts ; End of forg.