From:	eplmst AT lu DOT erisoft DOT se (Martin Stromberg)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Question about djgpp's int-wrapper
Date:	9 Jun 2002 10:22:57 GMT
Organization:	Ericsson Erisoft AB, Sweden
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Martin Steuer (martinSteuer AT gmx DOT de) wrote:
: The problem i mean is that the DPMI Specification says that non-priviledged 
: code may not be able to alter the IF via 'popf' or 'iret'.
: Therefore the DPMI Spec. suggests to insert a 'sti' before an 'iret' in 
: hardware interrupt handlers, because 'sti' is a priviledged instruction it 
: will be trapped and the DPMI Host will then execute an 'sti' in Ring0.

1. Where does it say that? 

2. IIRC, if sti is a priviledged instruction (because of IOPL < 3),
then iret and popf are too. So why would an emulated sti set IF and
not an emulated iret or popf?


Right,

						MartinS

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