\hypertarget{interface_name}{}\subsection{Name}\label{name}
{\tt TV} - A fully functional line interface based on the CLI package.\hypertarget{interface_synopsis}{}\subsection{Synopsis}\label{synopsis}
{\tt TV}

Drops the caller into the TV interface.\hypertarget{interface_description}{}\subsection{Description}\label{description}
The {\tt TV} command provides an example of how to use CLI to build up a command line interface. CLI is complicated enough that it deserves a proper manual, but given our current time pressures that's not going to happen.

CLI is based on the old VMS Command Line Interface, so a good first source of documentation are the corresponding DEC manuals. Beyond that, try to reverse engineer this example. The model is a TV remote which can be used to control:

\begin{itemize}
\item The power \item The channel \item The brightness \item The contrast \item The mute function\end{itemize}
To start the example, just type {\tt TV} and the program will drop you into a subcommand mode with the prompt {\tt TV$>$ }. The two most useful commands at this point are {\tt help}, which will print a brief synopsis of available commands, and {\tt show}, which will list the current settings (if the power is on ... you didn't expect the TV to work with the power off did you!). Your first command should probably be {\tt power on}. 