BSD 4_3_Tahoe release

[unix-history] / usr / src / usr.bin / tty.c

/*
* Copyright (c) 1988 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley.  The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1988 Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)tty.c       4.2 (Berkeley) 7/6/88";
#endif /* not lint */

#include <stdio.h>

main(argc, argv)
       int argc;
       char **argv;
{
       int ch, sflag;
       char *t, *ttyname();

       sflag = 0;
       while ((ch = getopt(argc, argv, "s")) != EOF)
               switch((char)ch) {
               case 's':
                       sflag = 1;
                       break;
               case '?':
               default:
                       fputs("usage: tty [-s]\n", stderr);
                       exit(1);
               }

       t = ttyname(0);
       if (!sflag)
               puts(t ? t : "not a tty");
       exit(t ? 0 : 1);
}