1  /* Argp example #2 -- a pretty minimal program using argp
       2     Copyright (C) 1991-2023 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, see <https://www.gnu.org/licenses/>.
      16  */
      17  
      18  /* This program doesn't use any options or arguments, but uses
      19     argp to be compliant with the GNU standard command line
      20     format.
      21  
      22     In addition to making sure no arguments are given, and
      23     implementing a --help option, this example will have a
      24     --version option, and will put the given documentation string
      25     and bug address in the --help output, as per GNU standards.
      26  
      27     The variable ARGP contains the argument parser specification;
      28     adding fields to this structure is the way most parameters are
      29     passed to argp_parse (the first three fields are usually used,
      30     but not in this small program).  There are also two global
      31     variables that argp knows about defined here,
      32     ARGP_PROGRAM_VERSION and ARGP_PROGRAM_BUG_ADDRESS (they are
      33     global variables because they will almost always be constant
      34     for a given program, even if it uses different argument
      35     parsers for various tasks).  */
      36  
      37  #include <stdlib.h>
      38  #include <argp.h>
      39  
      40  const char *argp_program_version =
      41    "argp-ex2 1.0";
      42  const char *argp_program_bug_address =
      43    "<bug-gnu-utils@@gnu.org>";
      44  
      45  /* Program documentation.  */
      46  static char doc[] =
      47    "Argp example #2 -- a pretty minimal program using argp";
      48  
      49  /* Our argument parser.  The @code{options}, @code{parser}, and
      50     @code{args_doc} fields are zero because we have neither options or
      51     arguments; @code{doc} and @code{argp_program_bug_address} will be
      52     used in the output for @samp{--help}, and the @samp{--version}
      53     option will print out @code{argp_program_version}.  */
      54  static struct argp argp = { 0, 0, 0, doc };
      55  
      56  int
      57  main (int argc, char **argv)
      58  {
      59    argp_parse (&argp, argc, argv, 0, 0, 0);
      60    exit (0);
      61  }