Files and directories

The following command will display the same information that you see in the first part of the prompt. Make sure that you have selected (clicked on) the Terminal window first and then type the following command followed by the Enter key:

whoami

Your output should be similar to the following:

The output of the whoami command, sysadmin, displays the user name of the current user. Although in this case your username is displayed in the prompt, this command could be used to obtain this information in a situation when the prompt did not contain this information.

The next command also displays information contained in the prompt. To be able to see the name of the computer, or hostname, on which you are executing commands, type the following in the terminal:

hostname

Your output should be similar to the following:

From the output of this command, localhost, you are able to see the fully-qualified hostname of this computer. Many commands that are executed produce text output like this. You can change what output is produced by a command by using options after the name of the command.

Options for a command can be specified in several ways. Traditionally in UNIX, options were expressed by a hyphen followed by another character, for example: -s.

In Linux, options can sometimes also be given by two hyphen characters followed by a word, or hyphenated word, for example: --short.

Execute the hostname command again twice in the terminal, once with the option -s and again with the option --short. This will display the short version of the hostname.

hostname -s
hostname --short

Your output should be similar to the following:

The pwd command is used to display your current "location" or current "working" directory. Type the following command to display the working directory:

pwd

Your output should be similar to the following:

The current directory in the example above is /home/sysadmin. This is also referred to as yourhome directory, a special place where you have control of files and other users normally have no access. By default, this directory is named the same as your username and is located underneath the /home directory.

As you can see from the output of the command (/home/sysadmin) Linux uses the forward slash (/) to separate directories to make what is called a path. The initial forward slash represents the top level directory, known as the root directory. More information regarding files, directories and paths will be presented in later labs.

The tilde (~) character that you see in your prompt is also indicating what the current directory is. This character is a "shortcut" way to represent your home.

FYI: pwd stands for "print working directory". While it doesn't actually "print" in modern versions, older UNIX machines didn't have monitors and output of commands went to a printer, hence the funny name of pwd.

Keyword:

• Explore Bash features
• Use shell variables
• Understand how to use globbing
• Be able to make use of quoting