From: Martin Str|mberg <ams AT ludd DOT luth DOT se>
Message-Id: <200107110554.HAA03884@father.ludd.luth.se>
Subject: Re: DJDIR Windows 2000 investigation results #1
In-Reply-To: <Pine.SUN.3.91.1010711075258.1314B-100000@is> from Eli Zaretskii at "Jul 11, 2001 08:04:46 am"
To: djgpp-workers AT delorie DOT com
Date: Wed, 11 Jul 2001 07:54:10 +0200 (MET DST)
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According to Eli Zaretskii:
> 
> On Wed, 11 Jul 2001, Andrew Cottrell wrote:
> 
> > > So it seems like Windows 2000 doesn't support FAT32, either in its LFN
> > > API or at all.  Could you please set LFN=n and see if DJGPP.ENV can be
> > > read, even without removing 0x1000 from the value of BX?
> >
> > Tried this during the investigation and it worked okay.
> 
> So the non-LFN DOS functions do support the FAT32 bit, while LFN 
> functions don't.  Gosh, what a mess!

Well, as FAT16 partitions are documented (IIRC) to only support file
sizes up to ~2GiB, there's actually no need to support that flag for
non-FAT32 partition. Or perhaps WINDOZE NT does support larger files
than that as it supports FAT16 with 64kiB clusters?

> Given this information, I see several possible ways to solve the 
> problem.  But first, I'd like to understand more about this FAT32 bit in 
> function 716Ch of Int 21h.  Martin, did we actually check that this bit 
> is required for opening large files under LFN?  Perhaps we could throw 
> together a short test program which tries to read/write such a large 
> file, and test it on Windows 9X and on W2K; then we would know if the 
> flag is needed, and if so, on what systems.

I did. You can't create bigger files than ~2GiB without this flag on
WINDOZE 98.

So it looks like my FAT32 detection routines will be needed after
all. As the weather isn't too good today I'll what I can whip up 'til
tonight.


Right,

						MartinS