; FCB layout
; 1 byte drive (0=default, 1=A:, 2=B:, ...)
; 8.3 filename
; 8.3 filename for rename

FCBDEN:	equ 23 ; WORD directory entry number
FCBSIZ:	equ 30

section .text

		; auto-complete drive field in fcb
		; IN	es:bx	far ptr FCB
		; OUT	si	copy of bx
fixfcb:		cmp byte [es:bx], 0
		jne .ret
		call getdd
		inc dl
		mov byte [es:bx], dl
.ret:		ret

		; Load root directory entry
		; IN	ax	number of directory entry
		; OUT	cs:si	ptr to directory entry
lddir:		push ax
		mov cl, 4
		shr ax, cl
		xor dx, dx
		call maprd
		; get si to point to entry
		pop si
		mov cl, 5
		shl si, cl
		and si, 0x1FF
		add si, dskbuf
		ret

		; find first matching file
		; IN	ES:BX	input fcb
fndfst:		


open:
		ret