Message-Id:	<5.0.2.1.2.20020609104552.009e64e0@pop.gmx.net>
X-Sender:	martinSteuer AT gmx DOT de@pop.gmx.net
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Date:	Sun, 09 Jun 2002 11:05:27 +0200
To:	djgpp AT delorie DOT com
From:	Martin Steuer <martinSteuer AT gmx DOT de>
Subject:	Re: Question about djgpp's int-wrapper
Mime-Version:	1.0
Reply-To:	djgpp AT delorie DOT com

Hello,

 >If interrupts were enabled before the interrupt came along, the iret
 >that returns control to the interrupted code should enable them again
 >as the IF is set in the image on the stack.

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.

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