Hi guys,

to give a quick comment on the "triple timestamps in DOS"
discussion: I guess it is safe in MOST situations to use
those, but not in all. It could be a feature to use per
default only for FAT32 kernels, or it could be SYS CONFIG
switchable, to keep "classic" directory entries possible.

Even for FAT32 kernels, the next question would be if it
is good to put those timestamps on FAT16 and FAT12 drives.

The wikipedia item mentioned earlier already gives context:

https://en.wikipedia.org/w/index.php?title=Design_of_the_FAT_file_system&oldid=614948461#Directory_entry

Offset 0x0c: Windows VFAT file name case flags, possibly
extra file size bits in EDR-DOS (only if file has attrib
hidden-readonly-system to hide from big-unaware tools),..

Offset 0x0d: Create time 1/100ths of seconds or original
first char of deleted files for some undelete-helper-TSR

Offset 0x0e: Access key hash for various older DOSes, or
VFAT create time. Two bytes (16 bit value)

Offset 0x10: Undelete-helper-TSR backup of timestamp, or
VFAT create date. Two byte value.

Offset 0x12: File ownership or undelete-helper-TSR backup
of timestamp or VFAT last access date. Luckily the latter
is not on by default, otherwise it would write a lot: Word.

https://en.wikipedia.org/wiki/CONFIG.SYS - see "ACCDATE"

Offset 0x14: High 16 bit of FAT32 cluster number or extra
flags on some special DOS versions and OS/2.

I think FreeDOS could have (or maybe already has) logics
to only use those multi-use fields for extra timestamps
if they are found to be 0 when DOS is about to set them.
That could limit conflict with undelete-helpers and such.

Note that most of this thread is about how nice CREATION
timestamps and dates would be to have. Apparently nobody
missed the ACCESS dates yet ;-)

Cheers, Eric

PS: Also interesting is how Windows nowadays uses the two
FAT copies and a flag at their start for "transactions":

https://en.wikipedia.org/wiki/Design_of_the_FAT_file_system#CLUST_1
(see also the link to TFAT in that section)




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