rename — change
    the name of a file
Standard C Library (libc, -lc)
#include
  <stdio.h>
int
  
  rename(const
    char *from, const char
    *to);
int
  
  renameat(int
    fromfd, const char
    *from, int tofd,
    const char *to);
The
    rename()
    system call causes the link named from to be renamed
    as to. If to exists, it is first
    removed. Both from and to must
    be of the same type (that is, both directories or both non-directories), and
    must reside on the same file system.
The
    rename()
    system call guarantees that if to already exists, an
    instance of to will always exist, even if the system
    should crash in the middle of the operation.
If the final component of from is a symbolic
    link, the symbolic link is renamed, not the file or directory to which it
    points.
If from and
    to resolve to the same directory entry, or to
    different directory entries for the same existing file,
    rename()
    returns success without taking any further action.
The
    renameat()
    system call is equivalent to rename() except in the
    case where either from or to
    specifies a relative path. If from is a relative path,
    the file to be renamed is located relative to the directory associated with
    the file descriptor fromfd instead of the current
    working directory. If the to is a relative path, the
    same happens only relative to the directory associated with
    tofd. If the renameat() is
    passed the special value AT_FDCWD in the
    fromfd or tofd parameter, the
    current working directory is used in the determination of the file for the
    respective path parameter.
The rename() function returns the
    value 0 if successful; otherwise the value -1 is returned and
    the global variable errno is set to indicate the
    error.
The rename() system call will fail and
    neither of the argument files will be affected if:
  - [ENAMETOOLONG]
- A component of either pathname exceeded 255 characters, or the entire
      length of either path name exceeded 1023 characters.
- [ENOENT]
- A component of the from path does not exist, or a
      path prefix of to does not exist.
- [EACCES]
- A component of either path prefix denies search permission.
- [EACCES]
- The requested link requires writing in a directory with a mode that denies
      write permission.
- [EACCES]
- The directory pointed at by the from argument denies
      write permission, and the operation would move it to another parent
      directory.
- [EPERM]
- The file pointed at by the from argument has its
      immutable, undeletable or append-only flag set, see the
      chflags(2)
      manual page for more information.
- [EPERM]
- The parent directory of the file pointed at by the
      from argument has its immutable or append-only flag
      set.
- [EPERM]
- The parent directory of the file pointed at by the
      to argument has its immutable flag set.
- [EPERM]
- The directory containing from is marked sticky, and
      neither the containing directory nor from are owned
      by the effective user ID.
- [EPERM]
- The file pointed at by the to argument exists, the
      directory containing to is marked sticky, and
      neither the containing directory nor to are owned by
      the effective user ID.
- [ELOOP]
- Too many symbolic links were encountered in translating either
    pathname.
- [ENOTDIR]
- A component of either path prefix is not a directory.
- [ENOTDIR]
- The from argument is a directory, but
      to is not a directory.
- [EISDIR]
- The to argument is a directory, but
      from is not a directory.
- [EXDEV]
- The link named by to and the file named by
      from are on different logical devices (file
      systems). Note that this error code will not be returned if the
      implementation permits cross-device links.
- [ENOSPC]
- The directory in which the entry for the new name is being placed cannot
      be extended because there is no space left on the file system containing
      the directory.
- [EDQUOT]
- The directory in which the entry for the new name is being placed cannot
      be extended because the user's quota of disk blocks on the file system
      containing the directory has been exhausted.
- [EIO]
- An I/O error occurred while making or updating a directory entry.
- [EINTEGRITY]
- Corrupted data was detected while reading from the file system.
- [EROFS]
- The requested link requires writing in a directory on a read-only file
      system.
- [EFAULT]
- Path points outside the process's allocated address space.
- [EINVAL]
- The from argument is a parent directory of
      to, or an attempt is made to rename
      ‘.’ or
      ‘..’.
- [EINVAL]
- The last component of the to path is invalid on the
      target file system.
- [ENOTEMPTY]
- The to argument is a directory and is not
    empty.
- [ECAPMODE]
- rename() was called and the process is in
      capability mode.
In addition to the errors returned by the
    rename(), the renameat() may
    fail if:
  - [EBADF]
- The from argument does not specify an absolute path
      and the fromfd argument is neither
      AT_FDCWDnor a valid file descriptor open for
      searching, or the to argument does not specify an
      absolute path and the tofd argument is neitherAT_FDCWDnor a valid file descriptor open for
      searching.
- [ENOTDIR]
- The from argument is not an absolute path and
      fromfd is neither AT_FDCWDnor a file descriptor associated with a directory, or the
      to argument is not an absolute path and
      tofd is neitherAT_FDCWDnor
      a file descriptor associated with a directory.
- [ECAPMODE]
- AT_FDCWDis specified and the process is in capability mode.
- [ENOTCAPABLE]
- path is an absolute path or contained a
      ".." component leading to a directory outside of the directory
      hierarchy specified by fromfd or
      tofd.
- [ENOTCAPABLE]
- The fromfd file descriptor lacks the
      CAP_RENAMEAT_SOURCEright, or the
      tofd file descriptor lacks theCAP_RENAMEAT_TARGETright.
The rename() system call is expected to
    conform to ISO/IEC 9945-1:1996
    (“POSIX.1”). The renameat()
    system call follows The Open Group Extended API Set 2 specification.
The renameat() system call appeared in
    FreeBSD 8.0.