sysdeps/mach/hurd/sethostid.c

   1 /* Copyright (C) 1993, 1996, 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library 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 GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <unistd.h>
  20 #include <hurd.h>
  21 #include "hurdhost.h"
  22 #include <stdio-common/_itoa.h>
  23
  24 /* Set the current machine's Internet number to ID.
  25    This call is restricted to the super-user.  */
  26 /* XXX should be __sethostid?
  27        isn't hostid supposed to be hardwired and unchangeable? */
  28 int
  29 sethostid (id)
  30      long int id;
  31 {
  32   char buf[8], *bp;
  33   ssize_t n;
  34
  35   /* The hostid is kept in the file /etc/hostid,
  36      eight characters of upper-case hexadecimal.  */
  37
  38   bp = _itoa_word (id, &buf[sizeof buf], 16, 1);
  39   while (bp > buf)
  40     *--bp = '0';
  41
  42   n = _hurd_set_host_config ("/etc/hostid", buf, sizeof buf);
  43   return n < 0 ? -1 : 0;
  44 }