sysdeps/posix/rename.c

   1 /* Copyright (C) 1991, 1992 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 Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 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 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <ansidecl.h>
  20 #include <stdio.h>
  21 #include <unistd.h>
  22 #include <errno.h>
  23
  24 /* Rename the file OLD to NEW.  */
  25 int
  26 DEFUN(rename, (old, new), CONST char *old AND CONST char *new)
  27 {
  28   int save = errno;
  29   if (__link(old, new) < 0)
  30     {
  31       if (errno == EEXIST)
  32         {
  33           errno = save;
  34           /* Race condition, required for 1003.1 conformance.  */
  35           if (__unlink(new) < 0 ||
  36               __link(old, new) < 0)
  37             return -1;
  38         }
  39       else
  40         return -1;
  41     }
  42   if (__unlink(old) < 0)
  43     {
  44       save = errno;
  45       if (__unlink(new) == 0)
  46         errno = save;
  47       return -1;
  48     }
  49   return 0;
  50 }