> ## 5 tty - A command line interface

> `tty` is a simple command line interface program where keystrokes are collected and interpreted. Completed lines are sent to the shell for interpretation. There is a simple history mechanism, which saves previous lines. These can be edited before sending them to the shell. `tty` is started when Erlang is started with the command:

> erl

> `tty` operates in one of two modes:

> - normal mode, in which lines of text can be edited and sent to the shell.
> - shell break mode, which allows the user to kill the current shell, start multiple shells etc. Shell break mode is started by typing Control G.

> ### 5.1 Normal Mode

> In normal mode keystrokes from the user are collected and interpreted by `tty`. Most of the emacs line editing commands are supported. The following is a complete list of the supported line editing commands.

> Note: The notation `C-a` means pressing the control key and the letter `a` simultaneously. `M-f` means pressing the `ESC` key followed by the letter `f`.

> Key Sequence | Function
> C-a | Beginning of line
> C-b | Backward character
> M-b | Backward word
> C-d | Delete character
> M-d | Delete word
> C-e | End of line
> C-f | Forward character
> M-f | Forward word
> C-g | Enter shell break mode
> C-k | Kill line
> C-l | Redraw line
> C-n | Fetch next line from the history buffer
> C-p | Fetch previous line from the history buffer
> C-t | Transpose characters
> C-y | Insert previously killed text
> tty text editing

> ### 5.2 Shell Break Mode

> tty enters shell break mode when you type Control G. In this mode you can:

> - Kill or suspend the current shell
> - Connect to a suspended shell
> - Start a new shell

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