Converts a 64-bit file time to MS-DOS date and time values.
mov ax, 71A7h ; date and time format conversion
mov bl, 0 ; File Time To DOS Time
mov si, seg lpft ; see below
mov ds, si
mov si, offset lpft
int 21h
jc error
mov [DOSTime], cx
mov [DOSDate], dx
mov [MilliSeconds], bh ; number of 10ms intervals in 2 seconds
Clears the carry flag, and sets the BH, CX, and DX registers to these values if successful:
| BH | Number of 10 millisecond intervals in 2 seconds to add to the MS-DOS time. It can be a value in the range 0 to 199. |
| CX | MS-DOS time. The time is a packed 16-bit value with the following form: |
| Bits | Contents |
| 0–4 | Second divided by 2 |
| 5–10 | Minute (0–59) |
| 11–15 | Hour (0–23 on a 24-hour clock) |
| DX | MS-DOS date. The date is a packed 16-bit value with the following form: |
| Bits | Contents |
| 0–4 | Day of the month (1–31) |
| 5–8 | Month (1 = January, 2 = February, and so on) |
| 9–15 | Year offset from 1980 (that is, add 1980 to get the actual year) |
Otherwise, the function sets the carry flag and sets the AX register to an error value.
The MS-DOS date format can represent only dates between 1/1/1980 and 12/31/2107; this conversion fails if the input file time is outside this range.
The time in FILETIME must be Coordinated Universal Time (UTC). The MS-DOS time is local time.