Yes, I've noticed that but that wouldn't work if it were the first run. Say OP is running his tests in a testing environment to build a solution for his problem. After the first run .dir gets added, on the second run and the ones thereafter, if he does change the command between runs, he will not get .dir.dir and so on. But what if he wants to run this as a one command solution on another machine? Most likely OP just runs your commands to clean up his system so this doesn't apply but just thought it worth mentioning for completeness.