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Table 1641

Format of DOS 3.1-3.3x, DR DOS 5.0-6.0 system file tables and FCB tables:
Offset	Size	Description	)
 00h	DWORD	pointer to next file table (offset FFFFh if last)
 04h	WORD	number of files in this table
 06h  35h bytes per file
	Offset	Size	Description
	 00h	WORD	number of file handles referring to this file
	 02h	WORD	file open mode (see AX=6C00h, #01402 at AH=3Dh)
			bit 15 set if this file opened via FCB
	 04h	BYTE	file attribute (see #01420 at AX=4301h)
	 05h	WORD	device info word (see #01423 at AX=4400h)
			bit 15 set if remote file
			bit 14 set means do not set file date/time on closing
			bit 12 set means don't inherit on EXEC
			bits 5-0 drive number for disk files
	 07h	DWORD	pointer to device driver header if character device
			else pointer to DOS Drive Parameter Block
			  (see #01395 at AH=32h)
	 0Bh	WORD	starting cluster of file
	 0Dh	WORD	file time in packed format (see #01665 at AX=5700h)
			not used for character devices in DR DOS
	 0Fh	WORD	file date in packed format (see #01666 at AX=5700h)
			not used for character devices in DR DOS
	 11h	DWORD	file size
	---system file table---
	 15h	DWORD	current offset in file (may be larger than size of
			  file; INT 21/AH=42h does not check new position)
	---FCB table---
	 15h	WORD	counter for last I/O to FCB
	 17h	WORD	counter for last open of FCB
			(these are separate to determine the times of the
			  latest I/O and open)
	 19h	WORD	relative cluster within file of last cluster accessed
	 1Bh	WORD	absolute cluster number of last cluster accessed
			0000h if file never read or written???
	 1Dh	WORD	number of sector containing directory entry
			(see #01352)
	 1Fh	BYTE	number of dir entry within sector (byte offset/32)
	 20h 11 BYTEs	filename in FCB format (no path/period, blank-padded)
	 2Bh	DWORD	(SHARE.EXE) pointer to previous SFT sharing same file
	 2Fh	WORD	(SHARE.EXE) network machine number which opened file
			(Windows Enhanced mode DOSMGR uses the virtual machine
			  ID as the machine number; see INT 2F/AX=1683h)
	 31h	WORD	PSP segment of file's owner (see #01378 at AH=26h)
			  (first three entries for AUX/CON/PRN contain segment
			  of IO.SYS startup code)
	 33h	WORD	offset within SHARE.EXE code segment of
			  sharing record (see #01637) 0000h = none
SeeAlso: #01639,#01640,#01642

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