Date: Wed, 16 Aug 2000 12:50:28 +0200
From: "Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
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To: lauras AT softhome DOT net
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In-reply-to: <399A58A0.473D5E04@softhome.net> (message from Laurynas Biveinis
	on Wed, 16 Aug 2000 11:02:24 +0200)
Subject: Re: Patch: open() adjustment for symlinks
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> Date: Wed, 16 Aug 2000 11:02:24 +0200
> From: Laurynas Biveinis <lauras AT softhome DOT net>
> 
> One more thing is unclear: in open() there is another _open() call, if
> the first fail. I assume it is OK to get away with single _open() call
> in readlink(), if it has SH_DENYNO set?

I'm not sure I understand how readlink is going to call _open, but
opening a file with SH_DENYNO as the default is not always a good
idea.  Take a look at the table of sharing behavior in RBIL, under
function 3Dh of Int 21: at least for SHARE.EXE it seems to say that,
if the file is open by another program in compatibility mode, and you
open it with SH_DENYNO, it fails if the file is not read-only
(whatever that means), even if, like in readlink, you open the file
for read-only access.

So perhaps we need the same two-step dance in readlink as well, just
to be on the safe side.  This is a minefield, and we alrteady know
that RBIL doesn't tell the whole truth, either.