src/hostname.c

   1 /* hostname - set or print the name of current host system
   2    Copyright (C) 1994-1997, 1999 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 /* The official name of this program (e.g., no `g' prefix).  */
  29 #define PROGRAM_NAME "hostname"
  30
  31 #define AUTHORS "Jim Meyering"
  32
  33 #if !defined(HAVE_SETHOSTNAME) && defined(HAVE_SYSINFO) && \
  34      defined (HAVE_SYS_SYSTEMINFO_H) && defined(HAVE_LIMITS_H)
  35 # include <sys/systeminfo.h>
  36
  37 int
  38 sethostname (name, namelen)
  39      char *name;
  40      int namelen;
  41 {
  42   /* Using sysinfo() is the SVR4 mechanism to set a hostname. */
  43   int result;
  44
  45   result = sysinfo (SI_SET_HOSTNAME, name, namelen);
  46
  47   return (result == -1 ? result : 0);
  48 }
  49
  50 # define HAVE_SETHOSTNAME 1  /* Now we have it... */
  51 #endif
  52
  53 char *xgethostname ();
  54
  55 /* The name this program was run with. */
  56 char *program_name;
  57
  58 void
  59 usage (int status)
  60 {
  61   if (status != 0)
  62     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  63              program_name);
  64   else
  65     {
  66       printf (_("\
  67 Usage: %s [NAME]\n\
  68   or:  %s OPTION\n\
  69 Print or set the hostname of the current system.\n\
  70 \n\
  71   --help      display this help and exit\n\
  72   --version   output version information and exit\n\
  73 ")
  74              , program_name, program_name);
  75       puts (_("\nReport bugs to <bug-sh-utils@gnu.org>."));
  76     }
  77   exit (status);
  78 }
  79
  80 int
  81 main (int argc, char **argv)
  82 {
  83   char *hostname;
  84
  85   program_name = argv[0];
  86   setlocale (LC_ALL, "");
  87   bindtextdomain (PACKAGE, LOCALEDIR);
  88   textdomain (PACKAGE);
  89
  90   parse_long_options (argc, argv, PROGRAM_NAME, GNU_PACKAGE, VERSION,
  91                       AUTHORS, usage);
  92
  93 #ifdef HAVE_SETHOSTNAME
  94   if (argc == 2)
  95     {
  96       int err;
  97
  98       /* Set hostname to argv[1].  */
  99       err = sethostname (argv[1], strlen (argv[1]));
 100       if (err != 0)
 101         error (1, errno, _("cannot set hostname to `%s'"), argv[1]);
 102       exit (0);
 103     }
 104 #else
 105   if (argc == 2)
 106     error (1, 0,
 107            _("cannot set hostname; this system lacks the functionality"));
 108 #endif
 109
 110   if (argc == 1)
 111     {
 112       hostname = xgethostname ();
 113       if (hostname == NULL)
 114         error (1, errno, _("cannot determine hostname"));
 115       printf ("%s\n", hostname);
 116     }
 117   else
 118     {
 119       error (2, 0, _("too many arguments"));
 120       usage (1);
 121     }
 122
 123   exit (0);
 124 }