FCB

Format of File Control Block:

Offset	Size	Description
00h	BYTE	drive number (0 = default, 1 = A, etc)
FFh is not allowed (signals extended FCB, see XFCB)
01h	8 BYTEs	blank-padded file name
09h	3 BYTEs	blank-padded file extension
0Ch	WORD	current block number
0Eh	WORD	logical record size
10h	DWORD	file size
14h	WORD	date of last write (see #01666 at AX=5700h)
16h	WORD	time of last write (see #01665 at AX=5700h) (DOS 1.1+)
18h	8 BYTEs	reserved (see #01347,#01348,#01349,#01350,#01351)
20h	BYTE	record within current block
21h	DWORD	random access record number (if record size is > 64 bytes, high byte is omitted)

SeeAlso

XFCB