The text user interface (TUI) has been designed for character-based (aka "dump") terminals. This mode can be used to run your application on a text terminal hardware or in a terminal emulator.
In TUI mode, the application windows/forms will display within the current console/terminal window as shown.
Figure 1. Text mode rendering
By default, applications forms are displayed in graphical mode as described later in this section. In order to run your applications in text mode, set the FGLGUI environment variable to 0 (zero).
On UNIX™ platforms, you need to configure you terminal capabilities with environment variables with TERM, TERMINFO or TERMCAP environment variables.