🚀 go-pugleaf

Please email a cc of any reply to greg.boyko@zephyrtech.com.

Quick version of question:

Is it possible to call a function that resides in a DLL from inside a
global system hook?

Expanded description:

I have a global windows hook (intalled using SetWindowsHookEx) of type
WH_CALLWNDPROC. In the hook I check for the activation of a certain
window. When that window is activated, I want to call a function that
resides in a DLL. The function that I'm calling is a debugged module
written for a previous application, and is known to work well. When I
call it from inside the hook, however, the system crashes badly.

Right now I'd settle for being able to call something as simple as
MessageBox() from inside the hook. I cannot even do that right now. The
system crashes.

I've tried linking against the DLL's lib file at hook link time as well
as loading the DLL and the function dynamically at runtime. When I try
to load the DLL at runtime, I crash upon trying to load it. The DLL's
entry point does not execute.

I would be absolutely delighted if someone could tell me they have
successfully called MessageBox() from inside a hook function! There
must
be some little trick that I'm missing or some pit I don't know to
sidestep.

My development environment:

I'm using Borland C++ Builder 3.0 under windows 98.


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