manual/examples/testopt.c

   1 /* Example of Parsing Arguments with getopt.
   2    Copyright (C) 1991-2012 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU General Public License
   6    as published by the Free Software Foundation; either version 2
   7    of the License, or (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, if not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 /*@group*/
  19 #include <ctype.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <unistd.h>
  23
  24 int
  25 main (int argc, char **argv)
  26 {
  27   int aflag = 0;
  28   int bflag = 0;
  29   char *cvalue = NULL;
  30   int index;
  31   int c;
  32
  33   opterr = 0;
  34 /*@end group*/
  35
  36 /*@group*/
  37   while ((c = getopt (argc, argv, "abc:")) != -1)
  38     switch (c)
  39       {
  40       case 'a':
  41         aflag = 1;
  42         break;
  43       case 'b':
  44         bflag = 1;
  45         break;
  46       case 'c':
  47         cvalue = optarg;
  48         break;
  49       case '?':
  50         if (optopt == 'c')
  51           fprintf (stderr, "Option -%c requires an argument.\n", optopt);
  52         else if (isprint (optopt))
  53           fprintf (stderr, "Unknown option `-%c'.\n", optopt);
  54         else
  55           fprintf (stderr,
  56                    "Unknown option character `\\x%x'.\n",
  57                    optopt);
  58         return 1;
  59       default:
  60         abort ();
  61       }
  62 /*@end group*/
  63
  64 /*@group*/
  65   printf ("aflag = %d, bflag = %d, cvalue = %s\n",
  66           aflag, bflag, cvalue);
  67
  68   for (index = optind; index < argc; index++)
  69     printf ("Non-option argument %s\n", argv[index]);
  70   return 0;
  71 }
  72 /*@end group*/