From: kunst AT prl DOT philips DOT nl
Subject: Re: Communication between djgpp-applications and Windows-application
To: r_bock AT FRUST1 DOT STAR DOT BOSCH DOT DE (Rene Bock)
Date: Tue, 1 Mar 1994 13:14:15 +0100 (MET)
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu (DJGPP users list)


Rene Bock (r_bock AT star DOT bosch DOT de) writes:
> 
> I have to realize the communication between an djgpp-application and a 
> Windows-application (a Windows dll, compiled with MC Visual C -- to be more
> precise). The two applications exchange data of some 100 bytes,
> rather frequently.
> 
> My first approach used the DOS-filesystem to perform the data exchange. 
> But this turned out to be v e r y   s  l  o  w.
> 
> Now, what can I do next?  I think about two things:
> 
> 1.  use of common memory.
> 
> 2.  use of DDE.
> 
> 3.  link a djgpp library with a Windows application (or dll).
> 
> 
> Now my questions:
> 
> a)  Is it possible to realize one of the approaches mentioned obove?
> 
> b)  If it is, how can it be done?
> 
> c)  If not, are there any other possibilities to reach my goal?
> 

You can use common memory (method 1) below the dreadful 640k barrier.
This memory can be accessed from a DJGPP program by using calls to
dosmemget() and dosmemput(). This will work inside a Windows DOS box.
This seems to me the most straightforward approach to reach your goal.
Common memory in the order of 100 bytes doesn't eat away too much of
your precious 640k memory.

Regards,

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