From: sandmann AT clio DOT rice DOT edu (Charles Sandmann)
Message-Id: <9709291403.AA14863@clio.rice.edu>
Subject: Re: [malcolm AT manawatu DOT gen DOT nz: Fork source code.]
To: eliz AT is DOT elta DOT co DOT il (Eli Zaretskii)
Date: Mon, 29 Sep 1997 09:03:12 -0600 (CDT)
Cc: k3040e4 AT c210 DOT edvz DOT uni-linz DOT ac DOT at, dj AT delorie DOT com,
        djgpp-workers AT delorie DOT com
In-Reply-To: <Pine.SUN.3.91.970929100930.1917H-100000@is> from "Eli Zaretskii" at Sep 29, 97 10:10:33 am
Content-Type: text
Precedence: bulk

> Do we have any means to detect whether the DPMI host is IOPL 0 or
> IOPL 3?  If not, based on what you say, it seems that CLI/STI is a
> better choice, since most of the DPMI are IOPL 3.

PUSHF, then some tests.  I did read someplace that sometimes Windows
will do both depending on the context, but I never investigated.  It
would be interesting to see which are which.

> So any problems with IRET should be affecting us in any code that
> involves signals, no?

Yes, and I'm not sure we always handle the interrupt flag properly
in exceptions, either.  At one time there was an IRET in longjmp.