src/yes.c

   1 /* yes - output a string repeatedly until killed
   2    Copyright (C) 1991-1997, 1999-2004, 2007-2012 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  16
  17 /* David MacKenzie <djm@gnu.ai.mit.edu> */
  18
  19 #include <config.h>
  20 #include <stdio.h>
  21 #include <sys/types.h>
  22 #include <getopt.h>
  23
  24 #include "system.h"
  25
  26 #include "error.h"
  27 #include "long-options.h"
  28
  29 /* The official name of this program (e.g., no 'g' prefix).  */
  30 #define PROGRAM_NAME "yes"
  31
  32 #define AUTHORS proper_name ("David MacKenzie")
  33
  34 void
  35 usage (int status)
  36 {
  37   if (status != EXIT_SUCCESS)
  38     emit_try_help ();
  39   else
  40     {
  41       printf (_("\
  42 Usage: %s [STRING]...\n\
  43   or:  %s OPTION\n\
  44 "),
  45               program_name, program_name);
  46
  47       fputs (_("\
  48 Repeatedly output a line with all specified STRING(s), or 'y'.\n\
  49 \n\
  50 "), stdout);
  51       fputs (HELP_OPTION_DESCRIPTION, stdout);
  52       fputs (VERSION_OPTION_DESCRIPTION, stdout);
  53       emit_ancillary_info ();
  54     }
  55   exit (status);
  56 }
  57
  58 int
  59 main (int argc, char **argv)
  60 {
  61   initialize_main (&argc, &argv);
  62   set_program_name (argv[0]);
  63   setlocale (LC_ALL, "");
  64   bindtextdomain (PACKAGE, LOCALEDIR);
  65   textdomain (PACKAGE);
  66
  67   atexit (close_stdout);
  68
  69   parse_long_options (argc, argv, PROGRAM_NAME, PACKAGE_NAME, Version,
  70                       usage, AUTHORS, (char const *) NULL);
  71   if (getopt_long (argc, argv, "+", NULL, NULL) != -1)
  72     usage (EXIT_FAILURE);
  73
  74   if (argc <= optind)
  75     {
  76       optind = argc;
  77       argv[argc++] = bad_cast ("y");
  78     }
  79
  80   while (true)
  81     {
  82       int i;
  83       for (i = optind; i < argc; i++)
  84         if (fputs (argv[i], stdout) == EOF
  85             || putchar (i == argc - 1 ? '\n' : ' ') == EOF)
  86           error (EXIT_FAILURE, errno, _("standard output"));
  87     }
  88 }