Function 57h Get for Set File Date and Time
entry AH 57h
AL 00h Get Date and Time
BX handle
return CX date
DX time
01h Set Date and Time
BX handle
CX time bits:
0Bh-0Fh hours(0-23)
05h-0Ah minutes(0-59)
00h-04h 2 second increments (0-29)
DX date bits:
09h-0Fh year(relative to 1980)
05h-08h month(1-12)
00h-04h day(1-31)
return CF set if error
AX error code
note 1) The file must have been previously opened or created via a successful
call to Int21f3C,Int21f3D,Int21f5A or Int21f5B.
2) The date and time are in the format used in the directory, with bit 0
the rightmost, or least significant, bit. struc -Directory
3) If the 16-bit date for a file is set to zero, that file's date and time
are not displayed on directory listings.
4) A date and time set with this function will prevail, even if the file
is modified afterwards before the handle is closed.