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Mail Archives: djgpp-workers/1997/10/14/00:17:40

Date: Tue, 14 Oct 1997 17:19:14 +1100
From: Bill Currie <billc AT blackmagic DOT tait DOT co DOT nz>
Subject: Re: Should off_t become unsigned?
In-reply-to: <Pine.SUN.3.91.971013144224.11407I-100000@is>
To: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>, djgpp-workers AT delorie DOT com
Message-id: <199710140416.RAA10413@teleng1.tait.co.nz gatekeeper.tait.co.nz>
Organization: Tait Electronics Limited
MIME-version: 1.0
References: <199710130316 DOT QAA05322 AT teleng1 DOT tait DOT co DOT nz gatekeeper.tait.co.nz>
Comments: Authenticated sender is <billc AT blackmagic DOT tait DOT co DOT nz>

On 13 Oct 97 at 14:42, Eli Zaretskii wrote:

> One thing I'd like to know is how can you detect a FAT32 drive.
> Function 7302h of Interrupt 21h seems to be the starting point, but
> the Interrupt List doesn't explicitly tell that it fails for volumes
> which are not FAT32, and it also seems to indicate that this
> function only works on Windows 95, not in plain DOS 7.
> 
> Can you try this?  Thanks.
> 

I'll certainly try it and find out (dos7 vs w95 that is, I don't know 
if there are any w95 machines arround here with fat16).

However, as to detecting whether a drive has fat32, just read the 
boot sector (w95 allows disk reads, just not writes) and check the 
fat size (sector count), if it's zero, its fat32. If the os doen't 
support fat32, I don't think it will be able to read the disk and 
you'll get a read error (I'll try this with a hacked floppy, w95 
probably won't read it, but at least I'll find out if dos will (and 
OpenDos, which seems to accept screwy disks that dos won't)).
Bill
--
Leave others their otherness.

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