Function 57h (87) Get or Set a File's Date and Time
Gets or sets a file's date and time.
To get a file's date and time:
On entry: AH 57h
AL 00h
BX File handle
Returns: AX Error code if CF is set
CX Time
DX Date
To set a file's date and time:
On entry: AH 57h
AL 01h
BX File handle
CX Time
DX Date
Returns: AX Error code if CF is set
Error codes: 1 Invalid function number in AL
6 Invalid handle
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Function 57h gets or sets the date and time for a file that has been
opened with a file handle (such as with function 3Dh).
The date and time are defined as follows:
CX = Time = Hour * 2048 + Minute * 32 + Second / 2
DX = Date = (Year - 1980) * 512 + Month * 32 + Day
CX Bits Description
11 - 15 Hours (0..23)
5 - 10 Minutes (0..59)
0 - 4 Seconds/2 (0..30)
DX Bits Description
9 - 15 Year since 1980 (0..119)
5 - 8 Month (1..12)
0 - 4 Day (1..31)
Notes: Contrary to what some DOS documentation says, the
date and time are returned in the conventional
format, with the high-order part in CH and DH and
the low-order part in CL and DL.
Seealso:
This page last updated on Fri Nov 30 10:49:50 MSK 2001
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