Activating external executable from Calc spreadsheet on Mac

Many years ago I enabled an Excel spreadsheet as a GUI for large and computationally intensive FORTRAN executable running on a Mac, thereby providing parameter and data inputs and graphical output. It worked extraordinarily well, enabling both Excel and FORTRAN to do what each does best. The FORTRAN executable was stand-alone and initiated by a few lines of Visual BASIC code started by clicking a spreadsheet button. Data were exchanged through files. I didn’t need to do any systems-level coding. I don’t have that skill. Now I would like to do something similar with Libre Office. Suggestions and guidance would be greatly appreciated. Many thanks in advance.

May be you are looking for the shell runtime command: Funktion Shell

Correct me if I’m wrong, but this appears targeted to Windows OS. Is there something comparable for Mac OS?

Yes - you are wrong. Of course you need to provide the path to the executable using the format applying to your operating system. Hence on macOS you would need to use something like shell("/Applications/Firefox.app/Contents/MacOS/firefox") to start Mozilla Firefox

Thank you for this information. I am supposing that this would allow me to execute my external app from a Calc action. Assuming this works, how would I first, from Calc, write the app’s input parameters and data to a file, then read its output contained in another file back into the Calc spreadsheet?

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