Calling C1.52 library from DOS pascal 3.31

[oscillogoat]

I am trying to call the mmsystem library that comes from VC 1.52 from MS-DOS pascal 3.31. I am Using the waveInGetNumDevs to test with.
function waveInGetNumDevs:NumDevs:word; extern;
result:= waveInGetNumDevs;
The source compiles and successfully links but sends control back to Windows and gives the error "The program has performed an illegal operation and will be shut down."
When I use the lines
function waveInGetNumDevs:NumDevs:word; extern;
result:= waveInGetNumDevs;
and it compiles but I get the link error
L2029 '_waveingetnumdevs' unresolved external
waveInGetNumDevs is described as function UINT
I have also tried the above with pascal integer type instead of word.

Anybody got any ideas?

 

[lionelhill]

I don't know about your particular compilers, but Pascal and C tend to use slightly different code at the start and end of functions to handle the call. I'd almost expect you to end up with a messed up stack and a return into nowhere. This is probably a prime case for choosing one language or the other, or getting into the depths of assembly and handling of calls in high level languages.

 

[oscillogoat]

The Pascal 3.31 manual says you can do mixed language programming. I think the problem may be either calling C++ 1.52 (windows) from Pascal 3.31(DOS) or that my variable types are not matched.
I am willing to use assembly if necessary but would rather avoid it. I was hopping someone had actualy called C++ 1.52 from Pascal 3.31. In the mean time, I am going to see if I can call C++ 1.52 code that I have compiled from Pascal 3.31.

 

[dkdude]

You're trying to incorporate a win32 function call in a DOS program -that's why.

Use free pascal instead -it compiles to windows too. Here's the link:

http://www.freepascal.org/down-win32.html

Regards


Jakob

 

[oscillogoat]

Is that true for windows 95 calls from DOS?
Can I call DOS from windows 95?

 

[dkdude]

You are able to call DOS functions from Windows via the shell (command.com). Vice versa is not possible as far as I know.

But try out FreePascal. The environment and feel is much like ye good olde Turbo Pascal!

Or even better - if you feel up to it, go all the way : Delphi .... c",) Here's a trial version:

http://www.borland.com/products/downloads/download_delphi.html

Regards


Jakob

 

[oscillogoat]

How are the graphics on freepascal and delphi?
I use a lot of graphics primitives like setviewport, and setworld as well as graphics text.

 

[dkdude]

Delphi is a windows developemt pascal language. To what you need go for FreePascal -it supports simplistic graphics like you want (viewport etc.)

Regards


Jakob

 

[oscillogoat]

Thanks All.

I installed free pascal and have been converting the graphics today. I will start a new thread if I get stuck on the conversion.

 

[oscillogoat]

Did Not have much luck with free pascal. My program does a lot of bitwise graphics. I wanted to explore using vc++ 1.52 as the parrant and breaking up my dos pascal into modules.

I can compile the C++ code and the dos pascal module but I get an unresolved external maxparam error when I Link the object code.
FOR AN EXAMPLE PROTOTYPE
The C++ code has the lines
void __pascal maxparam(int __near * a, int __near * b);
main()
{
int a:=5;
int b:=7;
maxparam(&a,&b);
}

and the pascal has the lines

MODULE Psub;
PROCEDURE Maxparam (VAR a INTEGER; VAR b:integer);
BEGIN
IF a> b then
b:=a;
ELSE
a:=b;
END;
END.

I have tried making psub a static library and have also tried psub as an import file.

ANY IDEAS ON LINKING