src/hostname.c

   1 /* hostname - set or print the name of current host system
   2    Copyright (C) 94, 95, 96, 1997 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 2, or (at your option)
   7    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, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /* Jim Meyering <meyering@comco.com> */
  19
  20 #include <config.h>
  21 #include <stdio.h>
  22 #include <sys/types.h>
  23
  24 #include "system.h"
  25 #include "long-options.h"
  26 #include "error.h"
  27
  28 #if !defined(HAVE_SETHOSTNAME) && defined(HAVE_SYSINFO) && \
  29      defined (HAVE_SYS_SYSTEMINFO_H) && defined(HAVE_LIMITS_H)
  30 # include <sys/systeminfo.h>
  31
  32 int
  33 sethostname (name, namelen)
  34      char *name;
  35      int namelen;
  36 {
  37   /* Using sysinfo() is the SVR4 mechanism to set a hostname. */
  38   int result;
  39
  40   result = sysinfo (SI_SET_HOSTNAME, name, namelen);
  41
  42   return (result == -1 ? result : 0);
  43 }
  44
  45 # define HAVE_SETHOSTNAME 1  /* Now we have it... */
  46 #endif
  47
  48 char *xgethostname ();
  49
  50 /* The name this program was run with. */
  51 char *program_name;
  52
  53 static void
  54 usage (int status)
  55 {
  56   if (status != 0)
  57     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  58              program_name);
  59   else
  60     {
  61       printf (_("\
  62 Usage: %s [NAME]\n\
  63   or:  %s OPTION\n\
  64 Print the hostname of the current system.\n\
  65 \n\
  66   --help      display this help and exit\n\
  67   --version   output version information and exit\n\
  68 ")
  69              , program_name, program_name);
  70       puts (_("\nReport bugs to <bug-sh-utils@gnu.org>."));
  71     }
  72   exit (status);
  73 }
  74
  75 int
  76 main (int argc, char **argv)
  77 {
  78   char *hostname;
  79
  80   program_name = argv[0];
  81   setlocale (LC_ALL, "");
  82   bindtextdomain (PACKAGE, LOCALEDIR);
  83   textdomain (PACKAGE);
  84
  85   parse_long_options (argc, argv, "hostname", GNU_PACKAGE, VERSION, usage);
  86
  87 #ifdef HAVE_SETHOSTNAME
  88   if (argc == 2)
  89     {
  90       int err;
  91
  92       /* Set hostname to argv[1].  */
  93       err = sethostname (argv[1], strlen (argv[1]));
  94       if (err != 0)
  95         error (1, errno, "%s", argv[1]);
  96       exit (0);
  97     }
  98 #else
  99   if (argc == 2)
 100     error (1, 0,
 101            _("cannot set hostname; this system lacks the functionality"));
 102 #endif
 103
 104   if (argc == 1)
 105     {
 106       hostname = xgethostname ();
 107       if (hostname == NULL)
 108         error (1, errno, _("cannot determine hostname"));
 109       printf ("%s\n", hostname);
 110     }
 111   else
 112     {
 113       error (2, 0, _("too many arguments"));
 114       usage (1);
 115     }
 116
 117   exit (0);
 118 }