ti@D8LXQt:/etc/apt/sources.list.d$ cd /etc/apt/sources.list.d/ && cat * -s
cat: '*': No such file or directory
ti@D8LXQt:/etc/apt/sources.list.d$ ls
ti@D8LXQt:/etc/apt/sources.list.d$ ls -al
total 8
drwxr-xr-x 2 root root 4096 Mar 12  2016 .
drwxr-xr-x 6 root root 4096 Dec 11 22:23 ..