title: cannot remove files by using "rm -rf $(ls -1t /home/app/services/ | tail -n+3)"
body: <p>I recently want to clean my disk space, so I want to run some commands to delete files from my VM. There are some old files in the <code>/home/app/services/</code>dir. So I am trying to run <code>rm -rf $(ls -1t /home/app/services/ | tail -n+3)</code> to delete all others files except most recent 2 of them under <code>/home/app/services/</code>. But I found if I do not enter to this dir, then this command will never work. It will only work if I entered that dir. Any idea that I can run this without entering into this dir? Thanks a lot</p>