The disk transfer area address is set with Int 21H Function 1AH. The default DTA is a 128-byte buffer at offset 80H in the program segment prefix.Obtains the current address of the disk transfer area (DTA) for FCB file read/write operations.
Call with:
AH = 2FH
Returns:
ES:BX = segment:offset of disk transfer area
Note:
The disk transfer area address is set with Int 21H Function 1AH. The default DTA is a 128-byte buffer at offset 80H in the program segment prefix.
Example:
Obtain the current disk transfer area address and save it in the variable olddta.
olddta dd ? ; save disk transfer address
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mov ah,2fh ; function number
int 21h ; transfer to MS-DOS
; save it as DWORD pointer
mov word ptr olddta,bx
mov word ptr olddta+2,es
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