4.3BSD-Reno/src/usr.bin/tty/tty.1

.\" Copyright (c) 1990 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms are permitted provided
.\" that: (1) source distributions retain this entire copyright notice and
.\" comment, and (2) distributions including binaries display the following
.\" acknowledgement:  ``This product includes software developed by the
.\" University of California, Berkeley and its contributors'' in the
.\" documentation or other materials provided with the distribution and in
.\" all advertising materials mentioning features or use of this software.
.\" Neither the name of the University nor the names of its contributors may
.\" be used to endorse or promote products derived from this software without
.\" specific prior written permission.
.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
.\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
.\"
.\"     @(#)tty.1	6.3 (Berkeley) 6/24/90
.\"
.TH TTY 1 "%Q"
.UC 7
.SH NAME
tty \- return user's terminal name
.SH SYNOPSIS
.B tty
[ -s ]
.SH DESCRIPTION
The
.I tty
utility writes the name of the terminal attached to standard input
to standard output.
The name that is written is the string returned by
.IR ttyname (3).
If the standard input is not a terminal, the message ``not a tty''
is written.
The options are as follows:
.TP
-s
Don't write the terminal name; only the exit status is affected
when this option is specified.
The
.I -s
option is deprecated in favor of the ``test -t 0'' command.
.PP
.I Tty
exits 0 if the standard input is a terminal, 1 if the standard input is
not a terminal, and >1 if an error occurs.
.SH SEE\ ALSO
test(1), ttyname(3)
.SH STANDARDS
The
.I tty
function is expected to be POSIX 1003.2 compatible.