usr/src/usr.bin/tty/tty.1

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.\"     @(#)tty.1       6.2 (Berkeley) %G%
.\"
.TH TTY 1 ""
.AT 3
.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.