For scripting with omc: https://build.openmodelica.org/Document … pting.html

There is no other API as of yet (assuming you consider the CORBA interface the same as mos-scripting)

Is FMI relevant here?  OpenModelica exports FMU's, and I'm also wondering if an FMU can be used to simulate a model outside of the context of any tools by using the .dll's or source code?

I'm looking at the FMI documentation, but any heads-up would be appreciated in terms of whether or not FMI can do what I hope it does. 

Thanks again!

"Scripting" is basically putting omc commands into an .mos file and running it with omc right?

Yes. Scripting is like a mos-script. You can also use popen and read/write using stdin and stdout though. Or named pipes, etc.

FMI is different from the OMC API. You can use it to control a simulation, but that's about it.

Can you use the contents of an FMU to modify a simulation configuration (start time, stop time, increment, initial values of variables, parameters, etc.),  run that simulation, and then get the output (i.e. a csv)?  And all of this outside of the context of ANY tool?  (FMU's include the solvers used for a simulation, right?  Even if they're hidden in .dll's?)

Thanks for your help sjoelund!

You can do this without using FMU and without recompling the executable (parameter sweeps).
Simply use the buildModel command to create the executable, and then modify the command-line switches sent to the executable or modify the xml-file.