How To Run/Call A Script From An EA


I want to write a program that maximises abstraction so i can easily plug in components without having to touch other files. I planned on doing this by having eg a file that contains the function that gives buy and sell signals. This function will then write its signal to a file, which is read by the main program. This way it doesn't matter how the signal is generated as long as it is written to a file. How can i get the EA to call this auxiliary file (script)?

in normal C++ i would use System(), but i cannot find the mql5 alternative anywhere in the reference book.

Thank you