When you start the Builder, it attempts to use the host system's windowing package. If the Builder is started on a machine with a color monitor, it defaults to color.If MULTI is invoked from a non-windowing monitor or encounters problems with the window interface, it comes up in non-GUI mode. If MULTI is incorrectly coming up in non-GUI mode, check that the DISPLAY environment variable is set, or set it from the command line with the -display option.
If you start MULTI with the -nodisplay command line option, or if MULTI cannot start in GUI mode, then it will start in non-GUI mode in the Debugger. Because the Builder and Editor are available only in GUI mode, the Debugger is always displayed in non-GUI mode in these scenarios.