php man page for tty

TTY(1)								   User Commands							    TTY(1)

NAME
       tty - print the file name of the terminal connected to standard input

SYNOPSIS
       tty [OPTION]...

DESCRIPTION
       Print the file name of the terminal connected to standard input.

       -s, --silent, --quiet
	      print nothing, only return an exit status

       --help display this help and exit

       --version
	      output version information and exit

AUTHOR
       Written by David MacKenzie.

REPORTING BUGS
       GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
       Report tty translation bugs to <http://translationproject.org/team/>

COPYRIGHT
       Copyright (C) 2017 Free Software Foundation, Inc.  License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
       This is free software: you are free to change and redistribute it.  There is NO WARRANTY, to the extent permitted by law.

SEE ALSO
       Full documentation at: <http://www.gnu.org/software/coreutils/tty>
       or available locally via: info '(coreutils) tty invocation'

GNU coreutils 8.28						   January 2018 							    TTY(1)