Date: Thu, 25 Dec 1997 18:57:24 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Grigoriy Strokin <grg AT philol DOT msu DOT ru>
cc: djgpp AT delorie DOT com
Subject: Re: Fw: Long file names under Windows NT
In-Reply-To: <01bd114e$c665bf00$8f76e8c1@isabase.philol.msu.ru>
Message-ID: <Pine.SUN.3.91.971225185129.21392A-100000@is>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Precedence: bulk


On Thu, 25 Dec 1997, Grigoriy Strokin wrote:

> Please tell me how to make all DJGPP GNU utilities see long file names under
> Windows NT 4.0.
> I seem to have looked through all FAQs and DOCs, but thay only mention that
> long file names are supported under Windows 95.

The FAQ clearly says (in section 3.3) that the long file names are NOT 
supported on NT.  Here's an excerpt from that section:

  Note that the long filename API (the special LFN-aware functions of Int 21h)
  for DOS box is not supported by current versions of Win/NT, so you cannot
  have long filenames there from DJGPP programs.

Somebody is working on a solution for this, so this situation may change 
in the near future.  Until then, blame Microsoft.

> I have investigated how _use_lfn.c module determines whether to use LFN
> support. It DOS (int 21h) function  number
> 71h to get volume information, and disables LFN if 7100h is returned in AX,
> and NT returns exactly that value. Why?

Because NT doesn't support those functions of Int 21h.

> What does this mean? That NT is worse in supporting LFN?

The DJGPP LFN support is based on certain functions of DOS Int 21h.  The 
NT DOS box doesn't support these functions, it's as simple as that.  
Native NT programs can see long names because they don't use the Int 21h 
interface, but DOS programs such as what DJGPP produces don't have access 
to long names on NT.