"Master-file" for global definitions?
 

Dear all,

At the moment I am trying to implement a variable that is generally available within OpenFOAM. I have even gone as far as thinking about it being implemented as a pointer only.
Nevertheless all the ideas come back to some crucial point: Is there anything like a "master-file" that contains something like the "main()"-function commonly seen in C++?

A second thought was to orient myself at the implementation of the variable "psi", which seems to be the variable that is solved for in any of the equations. (Am I right at that point?) But again: Where is this variable defined? Then I could use the same file as some kind of blueprint for implementing my variable that would be available at least at most points of the code...

Thanks for any answers already in advance!
Bernhard