I've written code in various flavors that use 3 different types of "glob". My experience with this is that: "friends don't tell other friends to glob"! I am quite sure that your program with the default glob works in your test cases, on your Operating System. You presented the most simple case of "give me all files in the directory that my program is running in". Some Monks figure that POSIX glob is the way to go. I've run into platform and Perl version problems with that. I figure that no glob is the way to go.

because it caused a separate process to start up.No. A Perl "use" statement doesn't cause that to happen.