13.5. View Directory Contents with ls
Now that you know how to change directories, it is time to learn how
to view the contents of these directories. Using the ls
command, you can display the contents of your current directory.
Many options are available with the ls
command. The ls command, by itself, does not show all
the files in the directory. Some files are hidden files (also called dot
files) and can only be seen with an additional option specified to the
ls command.
 | Tip |
|---|
| | To see all the options of the ls
command, you can read the man page by typing man
ls at a shell prompt. If you want to print the man page,
at the prompt type man ls | col -b | lpr.
|
Type the command ls -a. Now you will see files
that begin with dots.
Hidden files are mostly configuration files which set preferences in
programs, window managers, shells, and more. The reason they are hidden
is to help prevent any accidental tampering by the user. When you are
searching for something in a directory, you are not usually looking for
these configuration files, so keep them hidden to help avoid some screen
clutter when viewing directories at the shell prompt.
Viewing all the files using the ls -a command can
give you plenty of detail, but you can view still more information, by
adding more than one option.
If you want to see the size of a file or directory, when it was
created and more, just add the long option
(-l) to the ls -a command. This
command shows the file creation date, its size, ownership, permissions,
and more.
You do not have to be in the directory whose contents you want to
view to use the ls command. For example, to see
what is in the /etc/ directory from your home
directory, type:
The following is a short list of some options commonly used with
ls. Remember, you can view the full list by reading
the ls man page (man ls).
-a — all. Lists all the files in
the directory, including the hidden files
(.filename). The .. and
. at the top of your list refer to the parent
directory and the current directory, respectively.
-l — long. Lists details about
contents, including permissions (modes), owner, group, size,
creation date, whether the file is a link to somewhere else on the
system and where its link points.
-F — file type. Adds a symbol to the
end of each listing. These symbols include
/ to indicate a directory;
@ to indicate a symbolic link to
another file; and * to indicate an
executable file.
-r — reverse. Lists the contents of the
directory from back to front.
-R — recursive. This option lists the
contents of all directories below the current directory recursively.
-S — size. Sorts files by their sizes.
