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From: Stephen Leake <stephen.a.leake.1@gsfc.nasa.gov>
Newsgroups: comp.lang.ada
Subject: Re: Waiting for callbacks from dll on Win32
Date: 04 Nov 2002 16:09:53 -0500
Organization: NASA Goddard Space Flight Center (skates.gsfc.nasa.gov)
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Bj�rn Lundin <bjorn.lundin.nospam@swipnet.se> writes:

> Hello!
> I'm trying to make an interface to a c-dll that
> connects to an OPC-server (WTclient.dll)
> 
> It wants a pointer to a procedure, which I can provide 
> with an access value to a procedure in a protected object.

Calling a procedure in a protected object is _not_ the same as calling
a "normal" procedure; there are tasking issues involved.

Wrap the protected object call in a "normal" procedure, and use that
as the callback.

Even then, you have to worry about the Ada tasking vs the C tasking.
If you have an Ada main, you are probably ok.

-- 
-- Stephe