text: /* Copyright (C) 1991-2015 Free Software Foundation, Inc.
     This file is part of the GNU C Library.
  
     The GNU C Library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Lesser General Public
     License as published by the Free Software Foundation; either
     version 2.1 of the License, or (at your option) any later version.
  
     The GNU C Library 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
     Lesser General Public License for more details.
  
     You should have received a copy of the GNU Lesser General Public
     License along with the GNU C Library; if not, see
     <http://www.gnu.org/licenses/>.  */
  
  #include <stdio.h>
  #include <unistd.h>
  #include <errno.h>
  
  /* Rename the file OLD to NEW.  */
  int
  rename (old, new)
       const char *old;
       const char *new;
  {
    int save = errno;
    if (__link (old, new) < 0)
      {
        if (errno == EEXIST)
  	{
  	  __set_errno (save);
  	  /* Race condition, required for 1003.1 conformance.  */
  	  if (__unlink (new) < 0 ||
  	      __link (old, new) < 0)
  	    return -1;
  	}
        else
  	return -1;
      }
    if (__unlink (old) < 0)
      {
        save = errno;
        if (__unlink (new) == 0)
  	__set_errno (save);
        return -1;
      }
    return 0;
  }
  