Prototype file different for 32 and 64 Matlab?

Hello,

I generated a prototype file in order to access functions in a shared library. I generated the prototype file on a Matlab 32bit system, but am also using it with Matlab 64bit systems.

On Matlab 64bit systems, functions involving arguments of type float will behave strangely (i.e. a different value will be handed over to the shared library). Is that normal?

Do I need different prototype files on Matlab 64 than on Matlab 32?

Thanks for any insight

Answer 1

[Marc]

To give a little example of my problem:

I have following function in my shared library:

extern __declspec(dllexport) int setVelocity(int client,int handle,float velocity,int mode);

In my prototype file I have following:

fcns.name{fcnNum}='setVelocity'; fcns.calltype{fcnNum}='cdecl'; fcns.LHS{fcnNum}='int32'; fcns.RHS{fcnNum}={'int32', 'int32', 'single', 'int32'};

In a M file, that loads the shared library, I also have this function, which calls the shared library:

function [rtn ]= setVelocity(obj,client,handle,velocity,mode)
  handle_ = int32(handle);
  velocity_ = single(velocity);
  mode_ = int32(mode);
  [rtn ] = calllib(obj.libName,'setVelocity',client,handle_,velocity_,mode_);
end

While calling setVelocity works perfectly fine with the 32bit library and the 32bit Matlab, it doesn't work correctly with the 64bit library and the 64bit Matlab: the float value is "magically" turned into -2.0f or 0.0f when the library function is called. How can that be? Am I missing something important?