FPDL

Ensures your freedom by making sure that your software is actually yours. The GPL is nice but it is a bit forceful. It may ensure the freedom of the user but not the developer along with it. Then there is the idea that licenses should be simple for easy reading and understanding for the layman. That is where simple permissive licenses like MIT or ISC come in. They are exceptionally simple but say nothing about keeping source code open as they focus on credit and a no warranty clause. An issue with these licenses is giving people credit. When to do this is sometims pretty confusing especially since you had only copied a do-while loop with error handling for opening files. The rest of the algorithm in the program is arguably yours, and what is considered code theft requiring proper credit is subject to how cruel the project owner of the project you took from is.