tty.c revision 1.2 
11.1Scgd/*
21.1Scgd * Copyright (c) 1988 Regents of the University of California.
31.1Scgd * All rights reserved.
41.1Scgd *
51.1Scgd * Redistribution and use in source and binary forms, with or without
61.1Scgd * modification, are permitted provided that the following conditions
71.1Scgd * are met:
81.1Scgd * 1. Redistributions of source code must retain the above copyright
91.1Scgd *    notice, this list of conditions and the following disclaimer.
101.1Scgd * 2. Redistributions in binary form must reproduce the above copyright
111.1Scgd *    notice, this list of conditions and the following disclaimer in the
121.1Scgd *    documentation and/or other materials provided with the distribution.
131.1Scgd * 3. All advertising materials mentioning features or use of this software
141.1Scgd *    must display the following acknowledgement:
151.1Scgd *	This product includes software developed by the University of
161.1Scgd *	California, Berkeley and its contributors.
171.1Scgd * 4. Neither the name of the University nor the names of its contributors
181.1Scgd *    may be used to endorse or promote products derived from this software
191.1Scgd *    without specific prior written permission.
201.1Scgd *
211.1Scgd * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
221.1Scgd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
231.1Scgd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
241.1Scgd * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
251.1Scgd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
261.1Scgd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
271.1Scgd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
281.1Scgd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
291.1Scgd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
301.1Scgd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
311.1Scgd * SUCH DAMAGE.
321.1Scgd */
331.1Scgd
341.1Scgd#ifndef lint
351.1Scgdchar copyright[] =
361.1Scgd"@(#) Copyright (c) 1988 Regents of the University of California.\n\
371.1Scgd All rights reserved.\n";
381.1Scgd#endif /* not lint */
391.1Scgd
401.1Scgd#ifndef lint
411.2Smycroft/*static char sccsid[] = "from: @(#)tty.c	4.4 (Berkeley) 6/1/90";*/
421.2Smycroftstatic char rcsid[] = "$Id: tty.c,v 1.2 1993/08/01 18:04:12 mycroft Exp $";
431.1Scgd#endif /* not lint */
441.1Scgd
451.1Scgd#include <stdio.h>
461.1Scgd
471.1Scgdmain(argc, argv)
481.1Scgd	int argc;
491.1Scgd	char **argv;
501.1Scgd{
511.1Scgd	int ch, sflag;
521.1Scgd	char *t, *ttyname();
531.1Scgd
541.1Scgd	sflag = 0;
551.1Scgd	while ((ch = getopt(argc, argv, "s")) != EOF)
561.1Scgd		switch((char)ch) {
571.1Scgd		case 's':
581.1Scgd			sflag = 1;
591.1Scgd			break;
601.1Scgd		case '?':
611.1Scgd		default:
621.1Scgd			fputs("usage: tty [-s]\n", stderr);
631.1Scgd			exit(2);
641.1Scgd		}
651.1Scgd
661.1Scgd	t = ttyname(0);
671.1Scgd	if (!sflag)
681.1Scgd		puts(t ? t : "not a tty");
691.1Scgd	exit(t ? 0 : 1);
701.1Scgd}
71