🚀 go-pugleaf

In article <16C02748F.CSCHUBER@bcsc02.gov.bc.ca> CSCHUBER@bcsc02.gov.bc.ca writes:

>I've been having the same problem.  I don't have the answer for you but
>hopefully I can add to the problem description.  I've created a DLL, actually
>written by Michael Thompson (tommy@msc.cornell.edu).  The .DEF file contains
>LIBRARY PORTIO
>CODE PRELOAD EXECUTEONLY IOPL
>SEGMENTS _TEXT CLASS 'CODE' IOPL PRELOAD EXECUTEONLYSEGMENTS P@IOCODE CLASS 'COD
>EXPORTS
> @inp
> @outp
> @inpw
> @outpw

You need to remember to specify the number of words to transfer from
the stack.  This is important because the IOPL segment runs within a
different privilege ring, which has an independent stack.  During the
transition to ring 2 (IOPL), OS/2 will transfer the specified number
of 16-bit words from the callers stack to the ring 2 stack, which will
allow the functions to locate their arguments appropriately.

What you are probably running into with your exception is that the
functions are looking up in the stack expecting to see their arguments
and are overrunning the top of the stack since nothing was ever pushed
there.

I'm not sure I remember the exact definitions of these functions, but
I think it was something like:

		inp (unsigned)
		inpw (unsigned)
		outp (unsigned, int)
		outpw (unsigned unsigned)

so you're basically talking about one or two 16-bit arguments.  Just
change your exports to:

		inp 1
		inpw 1
		outp 2
		outpw 2

and I think you'll be ok.


--
-- David
--
/-----------------------------------------------------------------------\
 \              David Bolen             \  Internet: db3l@ans.net      /
  |   Advanced Network & Services, Inc.   \   Phone: (914) 789-5327   |
 / 100 Clearbrook Road, Elmsford, NY 10523  \   Fax: (914) 789-5310    \
\-----------------------------------------------------------------------/