life_under_Ubuntu about articles HOT 3 OPEN

  7       5     5
 user   group  world
 r+w+x  r+x    r+x
 4+2+1  4+0+1  4+0+1  = 755

  7       4      4
 user   group  world
 r+w+x    r      r
 4+2+1  4+0+0  4+0+0  = 744

sudo vi /etc/hostname
sudo vi /etc/hosts

find . -type f -exec sed -i.bak "s/foo/bar/g" {} \;