how multiple S functions communicate

Hello all

I'm writing three distinctive S-functions and there would be shared veriable btween them, I don't know how to do it, all what i found is communocation btween multiple intance of the same S-function which is not my case

thanks

[Walter Roberson]

See https://www.mathworks.com/help/simulink/ug/using-global-data-with-the-matlab-function-block.html