1 /* 2 * Copyright (c) 1988, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#) Copyright (c) 1988, 1993 The Regents of the University of California. All rights reserved. 34 * @(#)tty.c 8.1 (Berkeley) 6/6/93 35 * $FreeBSD: src/usr.bin/tty/tty.c,v 1.4.2.1 2001/07/30 10:16:47 dd Exp $ 36 * $DragonFly: src/usr.bin/tty/tty.c,v 1.2 2003/06/17 04:29:33 dillon Exp $ 37 */ 38 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <unistd.h> 42 43 static void usage __P((void)); 44 45 int 46 main(argc, argv) 47 int argc; 48 char **argv; 49 { 50 int ch, sflag; 51 char *t, *ttyname(); 52 53 sflag = 0; 54 while ((ch = getopt(argc, argv, "s")) != -1) 55 switch((char)ch) { 56 case 's': 57 sflag = 1; 58 break; 59 case '?': 60 default: 61 usage(); 62 } 63 64 t = ttyname(0); 65 if (!sflag) 66 puts(t ? t : "not a tty"); 67 exit(t ? 0 : 1); 68 } 69 70 static void 71 usage() 72 { 73 fprintf(stderr, "usage: tty [-s]\n"); 74 exit(2); 75 } 76