body: Some time ago I became a university student and with that I got an access to serveral programming tools, such as Jetbrains' products, for free. The licences I got are of course only for academic purposes, which got me wondering: How do they enforce these types of licenses? When you load a .cpp/.h/etc files in for example notepad you can't tell in which program they were typed before, so how do they know if that commercial code was written in a program with non-suited license for a such usage?
  
  
  Another thing I thought about is: How do you "free" your code from the license of the program you wrote it in? For example, if I copy the contents of my file written in editor XYZ (with license only for academic purposes) to an open source editor, can I still not distribute it? What if I wrote my source code in XYZ program, but futher changes occured in the open source program? Is that "old" part of the code is still under that program license?
  
  
  
title: Enforcement of programing tools licenses