ANONYMOUS wrote: Just try it. You won't be able to make a recursive loop in your file-system by just making directories and copying files. But you may accidentally make an 'infinitely' long chain of directories. But you can always interrupt the execution of your program, and then use rm -rf to clean any unwanted directories. But you may wish to ask yourself what it even means to synchronise a directory and one of its subdirectories, and what result you'd expect.