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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #ifndef lint 31 static const char copyright[] = 32 "@(#) Copyright (c) 1988, 1993\n\ 33 The Regents of the University of California. All rights reserved.\n"; 34 #endif /* not lint */ 35 36 #ifndef lint 37 #if 0 38 static char sccsid[] = "@(#)tty.c 8.1 (Berkeley) 6/6/93"; 39 #endif 40 #endif /* not lint */ 41 42 #include <sys/cdefs.h> 43 __FBSDID("$FreeBSD$"); 44 45 #include <stdio.h> 46 #include <stdlib.h> 47 #include <unistd.h> 48 49 static void usage(void); 50 51 int 52 main(int argc, char *argv[]) 53 { 54 int ch, sflag; 55 char *t; 56 57 sflag = 0; 58 while ((ch = getopt(argc, argv, "s")) != -1) 59 switch (ch) { 60 case 's': 61 sflag = 1; 62 break; 63 case '?': 64 default: 65 usage(); 66 } 67 68 t = ttyname(0); 69 if (!sflag) 70 puts(t ? t : "not a tty"); 71 exit(t ? 0 : 1); 72 } 73 74 static void 75 usage(void) 76 { 77 fprintf(stderr, "usage: tty [-s]\n"); 78 exit(2); 79 } 80