irix - tty (1)

     tty - get the name	of the terminal

     tty [ -l ]	[ -s ]

     tty prints	the path name of the user's terminal.

     -l	  prints the synchronous line number to	which the user's terminal is
	  connected, if	it is on an active synchronous line.

     -s	  inhibits printing of the terminal path name, allowing	one to test
	  just the exit	code.

				    EXIT CODES
		      2	  if invalid options were specified,
		      0	  if standard input is a terminal,
		      1	  otherwise.

     ``not on an active	synchronous line'' if the standard input is not	a
     synchronous terminal and -l is specified.
     ``not a tty'' if the standard input is not	a terminal and -s is not
     specified.