Environment Variable

DISPLAY

specifies where to draw the windows.

BRLCAD_ROOT

specifies where to find the root directory of the installed BRL-CAD package.

EDITOR

specifies which external editor to use when one is required.

FB_FILE

specifies the framebuffer to use when using applications that require a framebuffer.

TCL_LIBRARY

specifies where to look for Tcl files.

TK_LIBRARY

specifies where to look for Tk files.