rename.c revision 169696 
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 (const char *zfrom, const char *zto)
26{
27  if (link (zfrom, zto) < 0)
28    {
29      if (errno != EEXIST)
30	return -1;
31      if (unlink (zto) < 0
32	  || link (zfrom, zto) < 0)
33	return -1;
34    }
35  return unlink (zfrom);
36}
37