/* rename.c -- BSD compatible directory function for System V
   Copyright (C) 1988, 1990, 1992 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#ifndef STDC_HEADERS
extern int errno;
#endif

/* Rename file FROM to file TO.
   Return 0 if successful, -1 if not. */

int
rename (from, to)
     char *from;
     char *to;
{
  struct stat from_stats;

  if (stat (from, &from_stats))
    return -1;

  if (unlink (to) && errno != ENOENT)
    return -1;

  if (link (from, to))
    return -1;

  if (unlink (from) && errno != ENOENT)
    {
      unlink (to);
      return -1;
    }

  return 0;
}