This document is a Mac OS X manual page. Manual pages are a command-line technology for providing documentation. You can view these manual pages locally using the man(1) command. These manual pages come from many different sources, and thus, have a variety of writing styles.

This manual page is associated with the Mac OS X developer tools. The software or headers described may not be present on your Mac OS X installation until you install the developer tools package. This package is available on your Mac OS X installation DVD, and the latest versions can be downloaded from developer.apple.com.

For more information about the manual page format, see the manual page for manpages(5).

RENAME(2)                   BSD System Calls Manual                  RENAME(2)

NAME
     rename -- change the name of a file

SYNOPSIS
     #include <stdio.h>

     int
     rename(const char *old, const char *new);

DESCRIPTION
     The rename() system call causes the link named old to be renamed as new.  If new exists, it is first
     removed.  Both old and new must be of the same type (that is, both must be either directories or non-directories) nondirectories)
     directories) and must reside on the same file system.

     The rename() system call guarantees that an instance of new will always exist, even if the system
     should crash in the middle of the operation.

     If the final component of old is a symbolic link, the symbolic link is renamed, not the file or direc-tory directory
     tory to which it points.

CAVEAT
     The system can deadlock if a loop is present in the file system graph.  This loop takes the form of an
     entry in directory `a', say `a/foo', being a hard link to directory `b', and an entry in directory `b',
     say `b/bar', being a hard link to directory `a'.  When such a loop exists and two separate processes
     attempt to perform `rename a/foo b/bar' and `rename b/bar a/foo', respectively, the system may deadlock
     attempting to lock both directories for modification.

     Whether or not hard links to directories are supported is specific to the underlying filesystem imple-mentation. implementation.
     mentation.

     It is recommended that any hard links to directories in an underlying filesystem should be replaced by
     symbolic links by the system administrator to avoid the possibility of deadlocks.

RETURN VALUES
     A 0 value is returned if the operation succeeds, otherwise rename() returns -1 and the global variable
     errno indicates the reason for the failure.

ERRORS
     The rename() system call will fail and neither of the argument files will be affected if:

     [EACCES]           A component of either path prefix denies search permission.

     [EACCES]           The requested operation requires writing in a directory (e.g., new, new/.., or
                        old/..) whose modes disallow this.

     [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.

     [EFAULT]           Path points outside the process's allocated address space.

     [EINVAL]           Old is a parent directory of new, or an attempt is made to rename `.' or `..'.

     [EIO]              An I/O error occurs while making or updating a directory entry.

     [EISDIR]           new is a directory, but old is not a directory.

     [ELOOP]            Too many symbolic links are encountered in translating either pathname.  This is
                        taken to be indicative of a looping symbolic link.

     [ENAMETOOLONG]     A component of a pathname exceeds {NAME_MAX} characters, or an entire path name
                        exceeds {PATH_MAX} characters.

     [ENOENT]           A component of the old path does not exist, or a path prefix of new does not exist.

     [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.

     [ENOTDIR]          A component of either path prefix is not a directory.

     [ENOTDIR]          old is a directory, but new is not a directory.

     [ENOTEMPTY]        New is a directory and is not empty.

     [EPERM]            The directory containing old is marked sticky, and neither the containing directory
                        nor old are owned by the effective user ID.

     [EPERM]            The new file exists, the directory containing new is marked sticky, and neither the
                        containing directory nor new are owned by the effective user ID.

     [EROFS]            The requested link requires writing in a directory on a read-only file system.

     [EXDEV]            The link named by new and the file named by old are on different logical devices
                        (file systems).  Note that this error code will not be returned if the implementa-tion implementation
                        tion permits cross-device links.

CONFORMANCE
     The restriction on renaming a directory whose permissions disallow writing is based on the fact that
     UFS directories contain a ".." entry.  If renaming a directory would move it to another parent direc-tory, directory,
     tory, this entry needs to be changed.

     This restriction has been generalized to disallow renaming of any write-disabled directory, even when
     this would not require a change to the ".." entry.  For consistency, HFS+ directories emulate this
     behavior.

SEE ALSO
     open(2), symlink(7)

STANDARDS
     The rename() function conforms to IEEE Std 1003.1-1988 (``POSIX.1'').

4.2 Berkeley Distribution        June 4, 1993        4.2 Berkeley Distribution