making programs communicate && making a (simple) compiler

Hi, I would like to know if anyone has any ideas as to how I could make programs communicate. You see, I need a very basic multi-platform program that executes routines used by platform specific programs. Also, how would I go about making a compiler, just for some really basic scripting? (I can handle parsing, but I have no clue how to translate commands)

P.S. In case you're wondering, this is all for LEGO® Mindstorms® tools. My goal is to make a set of more flexible computer tools for the RCX® than ever made before.

The simplest portable way to set up interprocess communication is to use files. Simple, right?

As for writing a compiler, this will take some time even for the most rudimentary. Why? You have to parse data, generate all sorts of tables so that you can reference the data, generate the machine code, and place the output into the executable container, to oversimplify the process somewhat.

In short, not a weekend project. :)

This site has a lot of info on inter process communication and a lot of other usefull things.

http://www.cs.cf.ac.uk/Dave/C/

>I need a very basic multi-platform program that executes
>routines used by platform specific programs.

I'm sorry, I do not really understand.