Line data    Source code

       1             : /* print the hexadecimal identifier for the current host
       2             : 
       3             :    Copyright (C) 1997, 1999, 2000, 2001, 2002, 2003, 2004, 2007 Free
       4             :    Software Foundation, Inc.
       5             : 
       6             :    This program is free software: you can redistribute it and/or modify
       7             :    it under the terms of the GNU General Public License as published by
       8             :    the Free Software Foundation, either version 3 of the License, or
       9             :    (at your option) any later version.
      10             : 
      11             :    This program is distributed in the hope that it will be useful,
      12             :    but WITHOUT ANY WARRANTY; without even the implied warranty of
      13             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      14             :    GNU General Public License for more details.
      15             : 
      16             :    You should have received a copy of the GNU General Public License
      17             :    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
      18             : 
      19             : /* Written by Jim Meyering.  */
      20             : 
      21             : #include <config.h>
      22             : #include <getopt.h>
      23             : #include <stdio.h>
      24             : #include <sys/types.h>
      25             : 
      26             : #include "system.h"
      27             : #include "long-options.h"
      28             : #include "error.h"
      29             : #include "quote.h"
      30             : 
      31             : /* The official name of this program (e.g., no `g' prefix).  */
      32             : #define PROGRAM_NAME "hostid"
      33             : 
      34             : #define AUTHORS "Jim Meyering"
      35             : 
      36             : /* The name this program was run with, for error messages. */
      37             : char *program_name;
      38             : 
      39             : void
      40          30 : usage (int status)
      41             : {
      42          30 :   if (status != EXIT_SUCCESS)
      43          28 :     fprintf (stderr, _("Try `%s --help' for more information.\n"),
      44             :              program_name);
      45             :   else
      46             :     {
      47           2 :       printf (_("\
      48             : Usage: %s\n\
      49             :   or:  %s OPTION\n\
      50             : Print the numeric identifier (in hexadecimal) for the current host.\n\
      51             : \n\
      52             : "),
      53             :               program_name, program_name);
      54           2 :       fputs (HELP_OPTION_DESCRIPTION, stdout);
      55           2 :       fputs (VERSION_OPTION_DESCRIPTION, stdout);
      56           2 :       emit_bug_reporting_address ();
      57             :     }
      58          30 :   exit (status);
      59             : }
      60             : 
      61             : int
      62          33 : main (int argc, char **argv)
      63             : {
      64             :   unsigned int id;
      65             : 
      66             :   initialize_main (&argc, &argv);
      67          33 :   program_name = argv[0];
      68          33 :   setlocale (LC_ALL, "");
      69             :   bindtextdomain (PACKAGE, LOCALEDIR);
      70             :   textdomain (PACKAGE);
      71             : 
      72          33 :   atexit (close_stdout);
      73             : 
      74          33 :   parse_long_options (argc, argv, PROGRAM_NAME, PACKAGE_NAME, VERSION,
      75             :                       usage, AUTHORS, (char const *) NULL);
      76          30 :   if (getopt_long (argc, argv, "", NULL, NULL) != -1)
      77           5 :     usage (EXIT_FAILURE);
      78             : 
      79          25 :   if (optind < argc)
      80             :     {
      81          23 :       error (0, 0, _("extra operand %s"), quote (argv[optind]));
      82          23 :       usage (EXIT_FAILURE);
      83             :     }
      84             : 
      85           2 :   id = gethostid ();
      86             : 
      87             :   /* POSIX says gethostid returns a "32-bit identifier" but is silent
      88             :      whether it's sign-extended.  Turn off any sign-extension.  This
      89             :      is a no-op unless unsigned int is wider than 32 bits.  */
      90           2 :   id &= 0xffffffff;
      91             : 
      92           2 :   printf ("%08x\n", id);
      93             : 
      94           2 :   exit (EXIT_SUCCESS);
      95             : }