When using a graphics terminal running X, several shell environment variables must be specifically defined. The variables that must be defined or redefined are DISPLAY, TERM, and PATH.
To define the shell environment variables you will need to work in an X environment, follow these steps:
The DISPLAY variable defines the host (hostname), display, and screen to which output will be sent. Most users will have one display and one screen, signified by 0.0 in the variable definition. The PATH variable must be set to include the location of the X executables on your system, usually /usr/bin/X11. The TERM variable defines the terminal type to be ``xterm''.