1/* rename -- rename a file
2   This function is in the public domain. */
3
4/*
5
6@deftypefn Supplemental int rename (const char *@var{old}, const char *@var{new})
7
8Renames a file from @var{old} to @var{new}.  If @var{new} already
9exists, it is removed.
10
11@end deftypefn
12
13*/
14
15#include "ansidecl.h"
16#ifdef HAVE_CONFIG_H
17#include "config.h"
18#endif
19#include <errno.h>
20#ifdef HAVE_UNISTD_H
21#include <unistd.h>
22#endif
23
24int
25rename (zfrom, zto)
26     const char *zfrom;
27     const char *zto;
28{
29  if (link (zfrom, zto) < 0)
30    {
31      if (errno != EEXIST)
32	return -1;
33      if (unlink (zto) < 0
34	  || link (zfrom, zto) < 0)
35	return -1;
36    }
37  return unlink (zfrom);
38}
39