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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
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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.