stty [options] [modes]

Sets terminal I/O options for the current device. Without options, stty reports the terminal settings, where a ^ indicates the Control key, and ^' indicates a null value. Most modes can be switched using an optional preceding dash (-, shown in brackets). The corresponding description is also shown in brackets. As a privileged user, you can set or read settings from another device using the syntax:

stty [options] [modes] < device

stty is one of the most complicated Unix commands. The complexity stems from the need to deal with a large range of conflicting, incompatible, and nonstandardized terminal devices—everything from printing teletypes to CRTs to pseudoterminals for windowing systems. Only a few of the options are really needed for day-to-day use. stty sane is a particularly valuable one to remember.



Report all option settings.


Report current settings in BSD format.

-f file

Use file instead of standard input.


Report current settings in stty format.

Control modes


Hang up connection (set the baud rate to zero).


Set terminal baud rate to n (e.g., 19200).


[Enable] disable modem control.


[Disable] enable the receiver.


[Disable] enable output hardware flow control using RTS/CTS.

cs n

Select character size in bits (5 n 8).


[One] two stop bits per character.


[Don’t] hang up connection on last close.


Same as [-]hup.

ispeed n

Set terminal input baud rate to n.


[Don’t] ...

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