|  | /* rename -- rename a file | 
|  | This function is in the public domain. */ | 
|  |  | 
|  | /* | 
|  |  | 
|  | @deftypefn Supplemental int rename (const char *@var{old}, const char *@var{new}) | 
|  |  | 
|  | Renames a file from @var{old} to @var{new}.  If @var{new} already | 
|  | exists, it is removed. | 
|  |  | 
|  | @end deftypefn | 
|  |  | 
|  | */ | 
|  |  | 
|  | #include "ansidecl.h" | 
|  | #ifdef HAVE_CONFIG_H | 
|  | #include "config.h" | 
|  | #endif | 
|  | #include <errno.h> | 
|  | #ifdef HAVE_UNISTD_H | 
|  | #include <unistd.h> | 
|  | #endif | 
|  |  | 
|  | int | 
|  | rename (const char *zfrom, const char *zto) | 
|  | { | 
|  | if (link (zfrom, zto) < 0) | 
|  | { | 
|  | if (errno != EEXIST) | 
|  | return -1; | 
|  | if (unlink (zto) < 0 | 
|  | || link (zfrom, zto) < 0) | 
|  | return -1; | 
|  | } | 
|  | return unlink (zfrom); | 
|  | } |