# tty

_Peios / Using Peios / Peiosutils / System and processes_

> Print the name of the terminal connected to standard input.

`tty` prints the name of the terminal connected to standard input.

```
tty [options]
```

```
$ tty
/dev/pts/3
```

If standard input is not a terminal — because it has been redirected from a file or a pipe — `tty` prints `not a tty` instead.

That second behaviour is the useful one: a script can run `tty` to find out whether it is being run interactively or as part of a pipeline, and behave accordingly.

## Options

| Option | Effect |
|---|---|
| `-s`, `--silent` | Print nothing; report the answer only through the exit status. |

## Exit status

| Code | Meaning |
|---|---|
| `0` | Standard input is a terminal. |
| `1` | Standard input is not a terminal. |
| `2` | A usage error. |

Related content:

- [stty](/peios/using-peios/peiosutils/system-and-processes/stty.md)
- [System and processes](/peios/using-peios/peiosutils/system-and-processes/overview.md)