rename.c

早期freebsd实现

/* rename -- rename a file
   Copyright (C) 1992 Free Software Foundation, Inc.

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

Libiberty 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
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with libiberty; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

/* Rename a file.  */

#include <errno.h>

int
rename (zfrom, zto)
     char *zfrom;
     char *zto;
{
  if (link (zfrom, zto) < 0)
    {
      if (errno != EEXIST)
	return -1;
      if (unlink (zto) < 0
	  || link (zfrom, zto) < 0)
	return -1;
    }
  return unlink (zfrom);
}