src/bin/tty.c

   1 /*
   2  * Copyright 2001-2013 Haiku, Inc. All rights reserved.
   3  * Distributed under the terms of the MIT License.
   4  *
   5  * Authors:
   6  *                              Daniel Reinhold, danielre@users.sf.net
   7  */
   8
   9
  10 #include <stdio.h>
  11 #include <unistd.h>
  12
  13 #include <OS.h>
  14
  15
  16 void
  17 usage()
  18 {
  19         printf("Usage: tty [-s]\n"
  20                "Prints the file name for the terminal connected to standard input.\n"
  21                "  -s   silent mode: no output -- only return an exit status\n");
  22
  23         exit(2);
  24 }
  25
  26
  27 int
  28 main(int argc, char *argv[])
  29 {
  30
  31         if (argc > 2)
  32                 usage();
  33
  34         else {
  35                 bool silent = false;
  36
  37                 if (argc == 2) {
  38                         if (!strcmp(argv[1], "-s"))
  39                                 silent = true;
  40                         else
  41                                 usage();
  42                 }
  43
  44                 if (!silent)
  45                         printf("%s\n", ttyname(STDIN_FILENO));
  46         }
  47
  48         return (isatty(STDIN_FILENO) ? 0 : 1);
  49 }