1 /* 2 * Copyright (c) 1988 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 */ 17 18 #ifndef lint 19 char copyright[] = 20 "@(#) Copyright (c) 1988 Regents of the University of California.\n\ 21 All rights reserved.\n"; 22 #endif /* not lint */ 23 24 #ifndef lint 25 static char sccsid[] = "@(#)tty.c 4.2 (Berkeley) 07/06/88"; 26 #endif /* not lint */ 27 28 #include <stdio.h> 29 30 main(argc, argv) 31 int argc; 32 char **argv; 33 { 34 int ch, sflag; 35 char *t, *ttyname(); 36 37 sflag = 0; 38 while ((ch = getopt(argc, argv, "s")) != EOF) 39 switch((char)ch) { 40 case 's': 41 sflag = 1; 42 break; 43 case '?': 44 default: 45 fputs("usage: tty [-s]\n", stderr); 46 exit(1); 47 } 48 49 t = ttyname(0); 50 if (!sflag) 51 puts(t ? t : "not a tty"); 52 exit(t ? 0 : 1); 53 } 54