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From: rommel@Informatik.TU-Muenchen.DE (Kai-Uwe Rommel)
Newsgroups: comp.windows.ms.programmer
Subject: Re: GlobalDosAlloc not exported in libs?
Message-ID: <1991Mar12.081711.8270@Informatik.TU-Muenchen.DE>
Date: 12 Mar 91 08:17:11 GMT
References: <1991Feb13.165724.18629@linus.mitre.org> <1991Mar10.143402.12577@siesoft.co.uk>
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Organization: Technische Universitaet Muenchen, Germany
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In article <1991Mar10.143402.12577@siesoft.co.uk> mjc@siesoft.co.uk (Mark Carlin) writes:
>I would hazard a guess and suggest that if your intention is to
>communicate with a a DOS program, such as a TSR, then you may have another
>problem to follow; altering segment registers and issuing a software
>interrupt in in enhanced mode will cause a protection violation.
>To overcome this you may have to mess around with DPMI (DOS Protected
>Mode Interface).
You *can* issue software interrupts in 386 enhanced mode, at least to
the most often used vectors, such as 2F, the multiplex interrupt. I use
this a lot. Installing TSR's as INT-2F-handlers is always a good idea
because you cannot conflict with other TSR's that easy as if you choose
some other arbitrary one if you follow the INT-2F specifications.
Also, when issuing a software interrupt, you can pass the segment value
for the GlobalDosAlloc()ated block in an universal register and load it
into a segment register in real mode in your TSR.

Kai Uwe Rommel