ls -ld /usr
drwxr-xr-x 54  root sys  69 Apr  9 2018 /usr 
ls -ld /usr/include
drwxr-xr-x 117 root bin 436 Sep 25 22:10 /usr/include
ls -ld /usr/include/sys
drwxr-xr-x 25  root bin 628 Sep 25 22:09 /usr/include/sys