Date:	Tue, 14 Aug 2001 19:58:30 +0300
From:	"Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
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To:	sandmann AT clio DOT rice DOT edu
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In-reply-to:	<10108141550.AA12856@clio.rice.edu> (sandmann@clio.rice.edu)
Subject:	Re: Fw: Fstat.c patch
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> From: sandmann AT clio DOT rice DOT edu (Charles Sandmann)
> Date: Tue, 14 Aug 2001 10:50:54 -0500 (CDT)
> 
> > We need to find a way to determine the drive letter where a file lives
> > given only a handle on which that file is open...  Any ideas?
> 
> I've got a prototype for existing files.  We modify _open to convert 
> long name to short name, then do the open by short name.  The drive 
> letter is then correct.  But as noted, this doesn't work with device
> names at all.

Does the LFN open work with devices?  That is, if we use LFN open on
devices, can we then reliably determine that they are devices?

If so, this might be good enough: the st_dev member is fake for
devices anyway.

For devices, we need to be able to determine other attributes (those
which _get_dev_info returns and some others).  I think we need to test
all the IOCTL functions called by the library and see which open (SFN
or LFN) is better.

> For new files short of reopening I don't have a fix.

We should solve this as well, somehow.

> Another thought it to use the 71a6 information which provides a volume
> serial number - I'm not sure how we use this yet, but this might be
> better.

is there a way to find out the drive given the serial number?

> Note that on a valid handle 71a6 appears to fail for device handles,
> which may be another hint on how to deal with devices on W2K.

That's good to know, but I'm afraid I don't see how does it help with
any of the problems we are considering.  Are you suggesting to use the
failure as a sign of a device?  If so, we will need to find a way to
distinguish between a failure-because-device and a failure-because-
invalid-handle.

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