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@(#)tty.1 6.2 (Berkeley) 12/07/89

.AT 3 tty - return user's terminal name tty [ -s ] The 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 ttyname (3). If the standard input is not a terminal, the message ``not a tty'' is written. The options are as follows:

-s Don't write the terminal name; only the exit status is affected when this option is specified. The -s option is deprecated in favor of the ``test -t 0'' command.

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.

test(1), ttyname(3) The tty function is expected to be POSIX 1003.2 compatible.