Listing files and directories

You can list the files and subdirectories in your current directory (the one you are in at the moment) by entering ls and pressing the Enter key.

[sparc03]...kaputnik>ls
letter.txt      news            bin             hotstuff
mail            work            prog
[sparc03]...kaputnik>

The above list shows seven items in the directory. Some items are files and some are directories, but from this list there is no way of telling which are which. The ls command also does not normally list hidden files. Listing hidden files is explained below.

Distinguishing files from directories and executables

To get a listing that distinguishes directories and executables from files, use the -F option after the ls command. Using the above example, the ls -F command would give the following list

[sparc03]...kaputnik>ls -F
Letter.txt      News/           bin/            HotStuff/
Mail/           Work/           prog*
[sparc03]...kaputnik>

The -F option displays a slash (/) after directories and an asterisk (*) after executable files. From this list, you can see that

• Letter.txt is a file.
• prog is an executable file (a file you can run as a program).
• The other items are directories.

Getting information about the files

The -l option provides a long listing that displays the

• Unix file permissions
• File owners
• File sizes
• Modification dates
• File names

[sparc03]...kaputnik>ls -l
total 16
-rw-r--r--  1 kaputnik      1753 Feb 10 09:55 Letter.txt
drwx------  4 kaputnik      2048 Nov 8  11:12 Mail
drwxr-xr-x  3 kaputnik      2048 Jan 30 16:26 News
drwxr-xr-x 13 kaputnik      2048 Feb 10 09:52 Work
drwx------  3 kaputnik      2048 Oct 27 09:47 bin
-rwx------  2 kaputnik      9087 May 19 1992 prog
drwx------  2 kaputnik      2048 May 19 1992 HotStuff
[sparc03]...kaputnik>

The dash at the beginning of the first line means that item is a file and not a directory. The 'd' at the beginning of the second line identifies that item as a directory. The string of characters following the dash or 'd' designates the security on the file: who can view or otherwise manipulate the file. File security is explained in another section.

In the example above, kaputnik is the loginID of the file's owner. The number preceding the date indicates how many bytes the file or directory uses (the file's size). If the date is not one from the current year it will include only the month and year. The last field is the file or directory name.

Including both the -l and the -F options combines their effects to produce a comprehensive long listing:

[sparc03]...kaputnik>ls -lF
total 16
-rw-r--r--- 1 kaputnik    1753 Feb 10 09:55 Letter.txt
drwx------- 4 kaputnik    2048 Nov  8 11:12 Mail/
drwxr-xr-x  3 kaputnik    2048 Jan 30 16:26 News/
drwxr-xr-x 13 kaputnik    2048 Feb 10 09:52 Work/
drwx------- 3 kaputnik    2048 Oct 27 09:47 bin/
-rwx------- 2 kaputnik    9087 May 19  1992 prog*
drwx------- 2 kaputnik    2048 May 19  1992 HotStuff/
[sparc03]...kaputnik>

Listing hidden files

A file or directory whose name begins with a period (as in ".login") is known as hidden because commands such as ls don't normally list them. Entering the command ls -a (which means list all) will list hidden files and directories.

[sparc03]...kaputnik>ls -a
.login         News
.mylogin       Work
.mycshrc       bin
Letter.txt     HotStuff
Mail           prog
[sparc03]...kaputnik>

Files that are 'hidden' are called dotfiles because they have a dot (period) at the beginning. Although directories can be 'hidden' with a preceding dot (as in the ".elm" directory), you'll rarely hear anyone talking about dot-directories. This is because you don't usually alter a directory to change the way a program functions; you change the files inside the directory.

Dotfiles typically establish personal settings for programs and your Unix environment. For example, the ".mylogin" file is where you should put certain customizations.

You can create problems for yourself if you delete a hidden file required by the system or a program. Please read all sections of Customizing your account before you modify any of your hidden files.

Entering the command ls -al lists all files in current directory in a long list format.

Summary

ls list the contents of a directory (DOS equivalent is dir)

ls (quick list)

ls -l (detailed list)

ls -a (includes hidden files)

ls -al (shows all files)

Last modified July 20, 2004 by cawalker