8.2 Environment Variables

An example of an environment variable is the OSTYPE variable. The value of this is the current operating system you are using. Type

% echo $OSTYPE

More examples of environment variables are

• USER (your login name)
• HOME (the path name of your home directory)
• HOST (the name of the computer you are using)
• ARCH (the architecture of the computers processor)
• DISPLAY (the name of the computer screen to display X windows)
• PRINTER (the default printer to send print jobs)
• PATH (the directories the shell should search to find a command)

Finding out the current values of these variables.

ENVIRONMENT variables are set using the setenv command, displayed using the printenv or env commands, and unset using the unsetenv command.

To show all values of these variables, type

% printenv less