Calling dll funtions

General Usage
1

Hello, I decided to learn Julia in order to automate some data analysis and some experiments in the Lab, still, I am struggling with some simple things…

I am trying to call a couple of functions of a DLL file in order to interact with a spectrometer.
I was provided with an executable file that tests the dll functions, however, I would like to port this to Julia.

in the cpp file of this executable,

//CONNECT
	int *connect = classSpec::Connect();
	if (connect[0] == 0)
	{
		cout << "Connection failed!!!" << endl;
	}
		else
	{
		if (connect[1] == 0)//STD
		{
			cout << "spec std  connected!!!" << endl;
			nPixel = 2048;
		}
			if (connect[1] == 1)//RES+
		{
			cout << "spec res+ connected!!!" << endl;
			nPixel = 3648;
		}
		}

This returns an array wherein the first position we know if the connection was successful and in the second array the type of equipment.

In order to reproduce this, I suppose I should use ccall

connect =ccall(("function_name","libfile"), Ptr{Int32}, () )

and later on

unsafe_load(connect)

However, when I do this I can only access the status of the connection (1st position).

Any directions on how to proceed would be of great use,
thanks in advance.

2

Hi,

Since you are returning an array, try this

const CONNECT_SIZE = 2
connect = ccall((:function_name, "libfile"), stdcall, Ptr{NTuple{CONNECT_SIZE,Int32}}, ())
connect_ = unsafe_load(connect)
# then you will have to convert the NTuple to Array
connect_arr = collect(connect_)

Try to write your code between ``` like this

```julia
some julia code
`` `< remove the space
or c++
```cpp
some c++ code
`` `< remove the space
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