1/* Copyright (C) 1991-2022 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, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <stdio.h>
19#include <unistd.h>
20#include <errno.h>
21
22/* Rename the file OLD to NEW. */
23int
24rename (const char *old, const char *new)
25{
26 int save = errno;
27 if (__link (old, new) < 0)
28 {
29 if (errno == EEXIST)
30 {
31 __set_errno (save);
32 /* Race condition, required for 1003.1 conformance. */
33 if (__unlink (new) < 0
34 || __link (old, new) < 0)
35 return -1;
36 }
37 else
38 return -1;
39 }
40 if (__unlink (old) < 0)
41 {
42 save = errno;
43 if (__unlink (new) == 0)
44 __set_errno (save);
45 return -1;
46 }
47 return 0;
48}
49

source code of glibc/sysdeps/posix/rename.c