Accessing an mxarray when using codeGen to convert Matlab DLL to mex

Hello!

I have a *.DLL that performs some data modification on a vector:

   calllib( 'DLL64', 'CPP', pX, pY)

Where pX and pY are pointers to the input and output respectively.

In order to grab the data from pY, I had initially used:

    for n = 0:outLen-1
        pYn = pY + n;
        outVal(1+n, 1) = pYn.value;
    end

When I run this through the codeGen, I had an issue with pointer increment:

??? Integers can only be combined with integers of the same class, or scalar doubles.

Turns out that pX is a mxArray. I am certain that I am reading this incorrectly. But, gave it a shot anyway:

I added a coder.extrinsic

    coder.extrinsic('mxGetData');

Then I attempted to collect the data as follows:

        if coder.target('MATLAB')
            for n=0:outLen-1
                pYn = pY + n;
                outVal(1+n, 1) = pYn.value;
            end
        else
            outVal = zeros(outLen-1, 1);
            outVal = mxGetData(pY);
        end

Is there any way I could increment the pointer without offending the codeGen?

It errors during codeGen. Any help is appreciated! Thank you!