1 /* tty -- print the path of the terminal connected to standard input
2 Copyright (C) 1990, 1991 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
18 /* Displays "not a tty" if stdin is not a terminal.
19 Displays nothing if -s option is given.
20 Exit status 0 if stdin is a tty, 1 if not, 2 if usage error.
22 Written by David MacKenzie (djm@ai.mit.edu). */
26 #include <sys/types.h>
31 /* The name under which this program was run. */
34 /* If nonzero, return an exit status but produce no output. */
37 static struct option longopts[] =
39 {"silent", 0, NULL, 's'},
40 {"quiet", 0, NULL, 's'},
52 program_name = argv[0];
55 while ((optc = getopt_long (argc, argv, "s", longopts, (int *) 0)) != EOF)
86 Usage: %s [-s] [--silent] [--quiet]\n", program_name);