Question

I export functions from DLL and all of them need the same parameter (number N (integer)).
DLL function are called from LabVIEW always in same order (initialization, calculation clean up)

Is it possible to set parameter N just once? I mean just send it to initialization and somehow export it to the rest of functions? So it is not necessary to send N to all function manually.

extern "C" __declspec(export) void initialization( int N ){
  do initialization with N
}

extern "C" __declspec(export) void calculation(){
  I would like to use N here but keep calculation()
}

extern "C" __declspec(export) void clean_up(){
  I would like to use N here but keep clean_up()
}

Answer 1

You can make your variable a global, set it from the initialization method, and then just retrieve it inside the other methods.

You do this by declaring it extern and defining it in a single .c file.