Data retrieval in matlab 2018b

The following statement worked in MATLAB 2011a, but doesn't work in MATLAB 2018b:

fprintf(fid,'CLAW Version: %d\n', CLAWVersion.data(1));

CLAWVersion is an int32 Outport from the main model, and is set to a hard constant.

error message:
Undefined variable "CLAWVersion" or class "CLAWVersion.data".

There is a PostSaveFcn callback in the model with the following:

%CLAWVersion = get_param(gcb, 'MaskValues');
%CLAWVersion = CLAWVersion(7);

Both lines are commented out.   
I have tried every combination of the PostSaveFcn lines with the code line

What is the method of doing this in MATLAB 2018B?