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 
8 Renames a file from @var{old} to @var{new}.  If @var{new} already
9 exists, 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 
24 int
rename(const char * zfrom,const char * zto)25 rename (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