I am interested to know how to communicate with another program using 
Windows messaging from LabVIEW.  I did not develop the program with which I 
want to communicate.  The developer allows other programs to interact with 
it using Windows messaging.

I need to post messages to that application and receive messages from that 
application.  The application does not use Windows message ID's.  Instead it 
uses a message name.  The message ID can be determined using a Win32 call, 
RegisterWindowMessage().

National Instruments has an example LabVIEW 5.1 program with a C++ DLL that 
receives messages, although it does not post messages.  It works with 
message ID's.  Unfortunately, I cannot even get the C++ to compile using 
Microsoft C++ 6.0.  Something about "redefinition of Occur".

The developer of the application knows that they have customers who are 
interfacing with their software using LabVIEW.  The developer does not know 
the particulars.  But they did say that some big name companies are doing 
it.  Darn, I wish I had their budget.

I attempted to write a VB.NET 2.0 Windows control and use WndProc() to 
handle messages.  It just sat there.  Even when I called it from a VB.NET 
2.0 containing form.  It responds to messages from the application, but not 
from an external application.

I have a VB.NET 1.1 program that overrides WndProc() in the Windows form. 
It behaves.  I can receive messages and post messages.  Now if I can only 
teach LabVIEW how to do that!

I am an application programmer.  I did not expect to have to get this 
intimate with Windows.  Is there someone who has done this from LabVIEW or 
can steer me through some of the issues.  I would be delighted.

Thanks,
Hamilton Woods 

Accutrol wrote:
> I am interested to know how to communicate with another program using 
> Windows messaging from LabVIEW.  I did not develop the program with which I 
> want to communicate.  The developer allows other programs to interact with 
> it using Windows messaging.
> 
> I need to post messages to that application and receive messages from that 
> application.  The application does not use Windows message ID's.  Instead it 
> uses a message name.  The message ID can be determined using a Win32 call, 
> RegisterWindowMessage().
> 
> National Instruments has an example LabVIEW 5.1 program with a C++ DLL that 
> receives messages, although it does not post messages.  It works with 
> message ID's.  Unfortunately, I cannot even get the C++ to compile using 
> Microsoft C++ 6.0.  Something about "redefinition of Occur".
> 
> The developer of the application knows that they have customers who are 
> interfacing with their software using LabVIEW.  The developer does not know 
> the particulars.  But they did say that some big name companies are doing 
> it.  Darn, I wish I had their budget.
> 
> I attempted to write a VB.NET 2.0 Windows control and use WndProc() to 
> handle messages.  It just sat there.  Even when I called it from a VB.NET 
> 2.0 containing form.  It responds to messages from the application, but not 
> from an external application.
> 
> I have a VB.NET 1.1 program that overrides WndProc() in the Windows form. 
> It behaves.  I can receive messages and post messages.  Now if I can only 
> teach LabVIEW how to do that!
> 
> I am an application programmer.  I did not expect to have to get this 
> intimate with Windows.  Is there someone who has done this from LabVIEW or 
> can steer me through some of the issues.  I would be delighted.
> 
> Thanks, Hamilton Woods 
 
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