To get to our first destination, type cd /. The
directory / is the “root” directory; it is an absolute
path. If you think of the directory structure as an upside-down
(Australian) tree (root at top), the directory / is at the
top. Type pwd and see where you are. Type ls;
you should see that the directory home listed with several
other directories. On a Mac, this directory is /Users. Here
is what the directory structure looks like on a PC running Red Hat
Fedora Core 9. Yours may have a slightly different appearance.
unix> cd / unix> ls bin etc lib mnt root srv usr boot home lib64 opt run sys var cdrom initrd.img lost+found proc sbin tmp vmlinuz.old dev initrd.img.old media root selinux vmlinuz unix>
Now type if we type cd home then ls, you
will see one or more directories. On the machine being used here, you
would see
unix> cd home unix> ls guest lost+found morrison
This machine has two users, morrison and
guest. Since it is a personal computer, it does not have
many users. You may be working on a server in which there could be
dozens, or even hundreds of other users who are organized into various
directories.
Here is an example from a fairly busy server.
unix> cd /home unix> ls 2016 2018 2020 gotwals menchini rash 2017 2019 cs keethan.kleiner morrison rex.jeffries unix>
The directories with the years are directories full of user’s home directories. We will list one here. It has quite a few users in it.
unix> ls 2019 allen19m hablutzel19k laney19m mullane19n wang19e bounds19a hirsch19m lheem19h ou19j wolff19o carter19d hou19b lin19b overpeck19c yang19j cini19a houston19b liu19c perrin19p zhuang19a eun19e houston19p manocha19a sakarvadia19m gupta19a knapp19t mitchell19m villalpando-hernandez19j unix>
Try typing cd ..; the special symbol ..
represents the directory above your cwd. Now you can climb
up and down the directory structure! The .. symbol works
like the up-arrow in a file chooser dialog box in Mac or Windoze. You
saw this when you did the last group of exercises.
Practice this; go back to your home directory. Make a new directory
called mudpies. Put some files in it. Make new directories
in mudpies, got down inside these and make more directories
and files. Practice using cd to navigate the tree you
create. When you are done, get rid of the whole mess; remember you have
to go to the bottom, empty out the files using rm and then
use rmdir to get rid of the empty directories.